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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No.           )

Filed by the Registrant ☒
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Preliminary Proxy Statement

Confidential, for Use of the Commission Only (as permitted by Rule 14a 6(e)(2))

Definitive Proxy Statement

Definitive Additional Materials

Soliciting Material under §240.14a 12
Tetra Tech, Inc.
(Name of Registrant as Specified in Its Charter)
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Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a 6(i)(1) and 0-11.

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Filed by a Party other than the Registranto

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o


Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

ý


Definitive Proxy Statement

o


Definitive Additional Materials

o


Soliciting Material under §240.14a-12


Tetra Tech, Inc.

(Name of Registrant as Specified In Its Charter)

N/A

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

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Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.



(1)


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(2)Aggregate number of securities to which transaction applies:
(3)Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
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Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.



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Table of Contents


LOGO

3475 E. Foothill Boulevard
Pasadena, California 91107
(626) 351-4664
www.tetratech.com

NOTICETABLE OF ANNUAL
MEETING

AND

2018 PROXY STATEMENT

CONTENTS
Thursday, March 8, 201810:00 a.m. (PT)

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LOGO


LETTER TO STOCKHOLDERS
FROM OUR BOARD OF DIRECTORS

January 24, 2018

Dear Fellow Stockholder:

We thank you for your investment in

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Today, Tetra Tech, and for trusting us to represent you and oversee your interests in our Company.

The Board understands that we are elected by our stockholders to oversee the Company's long-term health and overall success. We are the Company's ultimate decision-making body, except for those matters reserved to or shared with stockholders, and we play a critical role in strategic planning.

We select, oversee and evaluate a very capable management team that conducts the day-to-day business of the Company and is optimistic about the future of this business. They have taken thoughtful and decisive steps to focus the business on "Leading with Science®," and providingTech’s high-end consulting and engineering services are more in demand than ever before. With our focus on Leading with Science®, we are ideally positioned to provide the sustainable solutions that are differentiatedneeded in a changing world.

Dan Batrack
Chairman and of long-lasting sustainable value to clients. The Company remains committed to delivering long-term value for our stockholders. Management and your Board are pleased to report a 91% increase in our total shareholder return over the last three years, and we remain optimistic about the Company's future.

One of our priorities is listening to the views of our stockholders and considering them as we make decisions in the boardroom. Through management, we engage with stockholders during an annual outreach cycle and, based on this engagement, we made significant enhancements to the Company's governance and compensation programs over the last few years.

Chief Executive Compensation

Our stockholders continue to tell us that a fundamental principle underlying any compensation program is that it should pay for performance. We agree, and our feedback from stockholders continues to contribute to our compensation decisions. Our Compensation Committee regularly assesses the Company's compensation programs, and the enhancements are designed to further align our business and talent strategies with the long-term interests of our stockholders.

Board Refreshment and Diversity

The issue of Board refreshment has emerged as an important area of focus for stockholders. We agree that new perspectives and new ideas are critical to a forward-looking and strategic Board. At the same time, it is also important to benefit from the valuable experience and insight that longer-serving Directors bring to the boardroom.

Ensuring diverse perspectives, including a mix of skills, experience and backgrounds, is key to effectively representing the long-term interests of our stockholders. Doing so is a top priority of the Board. In the last four years, three new Directors were elected and one long-term Director retired. As a result, the average tenure for our Directors has been reduced and our Board's gender diversity is currently one third women. Further, the Board determined that the role of Presiding Director would rotate to ensure independence,


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and the term of the Presiding Director would be limited to four years. We remain committed to ensuring that your Board is composed of a highly capable and diverse group of Directors, well-equipped to oversee the success of the business and effectively represent the interests of our stockholders.

Board Risk Oversight

The Board oversees the Company's risk profile and monitors the management of risks within the Company. The Strategic Planning and Enterprise Risk Committee has been tasked with coordinating the Board's risk oversight function. This Committee oversees our enterprise risk management policies and procedures, particularly in the areas of strategic, operational and compliance risk. Each of our other three Committees also oversees specific areas of risk management.

Cybersecurity is also a critical priority for the entire Company. The Strategic Planning and Enterprise Risk Committee receives reports from the Chief Information Officer regarding the Company's information technology systems, and dedicates time in its agenda for a discussion of cybersecurity and other important risk issues.

Board Accountability

As we conduct the activities of this Board, we consider accountability to stockholders as not only a mark of good governance, but a key to the long-term success of our Company. We remain accountable through a variety of governance practices, including:

      The annual election of all Directors;

      A majority vote bylaw in uncontested Director elections;

      An independent Presiding Director who presides over executive sessions of all independent directors;

      An annual Board evaluation process;

      The right of stockholders to call a special meeting;

      An annual advisory vote on executive compensation; and

      Proactive stockholder engagement.

Communicating with the Board

Finally, we value your input and encourage you to share your thoughts or concerns with us. To facilitate communication by stockholders, please address communications to the Tetra Tech Board of Directors in care of the Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107 or by email toasktheboard@tetratech.com.

As always, thank you for the trust you have placed in us.

January 2024
Dan L. BatrackHugh M. GrantPatrick C. Haden
J. Christopher LewisJoanne M. MaguireKimberly E. Ritrievi
Albert E. SmithJ. Kenneth ThompsonKirsten M. Volpi

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LOGO

January 24, 2018

Dear Tetra Tech Stockholders:

You are cordially invited to attend the 2024 Annual Meeting of Stockholders of Tetra Tech, Inc., which will be held at the Westin Pasadena, 191 N. Los Robles Avenue, Pasadena, California 91101, on Thursday, March 8, 2018,February 29, 2024, at 10:00 a.m. Pacific Time.

Details of the business to be conducted at the 2024 Annual Meeting are given in the accompanying Notice of 2024 Annual Meeting of Stockholders and the proxy statement.

We use the Internetinternet as our primary means of furnishing proxy materials to our stockholders. Consequently, most stockholders will not receive paper copies of our proxy materials. Wematerials and will instead send these stockholdersreceive a notice with instructions for accessing the proxy materials and voting via the Internet.internet. The notice also provides information on how stockholders maycan obtain paper copies of our proxy materials if they so choose. Internet transmission and voting are designed to be efficient, minimize cost, and conserve natural resources.

Whether or not you plan to attend the 2024 Annual Meeting, please vote as soon as possible. As an alternative to voting in person at the 2024 Annual Meeting, you may vote via the Internet,internet, by telephone, or if you receive a paper proxy card in the mail, by mailing the completed proxy card.mail. Voting by any of these methods will ensure your representation at the 2024 Annual Meeting.

Thank you for your continued support of Tetra Tech. We look forward to seeing you at the 2024 Annual Meeting.

Sincerely,
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Dan Batrack
Chairman and Chief Executive Officer



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3475 E. Foothill Boulevard, Pasadena, California 91107
(626) 351-4664
www.tetratech.com
Notice of 2024 Annual
Meeting of Stockholders
2024 Annual Meeting of Stockholders
DateThursday, February 29, 2024
TimeDan L. Batrack10:00 a.m. Pacific Time
PlaceChairman and Chief Executive OfficerWestin Pasadena
191 North Los Robles Avenue
Pasadena, California 91101
Record DateJanuary 2, 2024
Items of Business
ProposalBoard
Recommendation
Pasadena, CaliforniaItem 1To elect the seven directors nominated by our Board to serve a one-year term until the 2025 Annual Meeting of Stockholders (2025 Annual Meeting), and until their respective successors are duly elected and qualified or until his or her resignation or removalFOR
Item 2To approve, on an advisory basis, our named executive officers’ compensationFOR
Item 3To ratify the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for fiscal year 2024FOR
To transact such other matters that may properly come before the 2024 Annual Meeting or any postponement or adjournment thereof


TABLE OF CONTENTSYOUR VOTE IS IMPORTANT

In order


How to vote: Your vote is important
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InternetTelephoneMailIn Person
Follow the instructions provided in the Notice, separate proxy card, or voting instruction form you received.Follow the instructions provided in the separate proxy card or voting instruction form you received.Send your completed and signed proxy card or voting instruction form to the address on your proxy card or voting instruction form.You can vote in person at the 2024 Annual Meeting. Beneficial holders must contact their broker or other nominee if they wish to vote in person.
Dear Tetra Tech Stockholders:
Your vote is important. Even if you cannot attend the 2024 Annual Meeting, it is important that your shares be represented and voted. To ensure your representation at the 2024 Annual Meeting, you may submit your proxy and voting instructions via the Internet,internet, by telephone, or if you receive a paperby mail by following the instructions listed on your proxy card, andnotice, or voting instructions by mail, you may vote your shares by completing, signing and dating the proxy card as promptly as possible and returning it in the enclosed envelope. instruction form.
Please refer to the section entitled "Voting“Voting Your Shares"Shares” in theMeeting and Voting Information section on page 78 of thisthe accompanying proxy statement for a description of theseeach voting methods.method. If your shares are held by a bank, broker, or brokerage firmother nominee (your record holder) and you have not given your record holder instructions on how to do so,vote your brokershares, your record holder will NOTnot be able to vote your shares with respect toon any matter other than ratification of the appointment of the independent registered public accounting firm. We strongly encourage you to vote.


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LOGO


NOTICE OF 2018 ANNUAL MEETING OF STOCKHOLDERS

To Our Stockholders:

              You are cordially invited to attend our 2018 Annual Meeting of Stockholders to be held on Thursday, March 8, 2018, at 10:00 a.m. Pacific Time, at the Westin Pasadena, 191 N. Los Robles Avenue, Pasadena, California 91101. At the meeting, stockholders will vote on the following items of business:

              The record date for determining those stockholders who will be entitled to notice of, and to vote at, the Annual Meeting and any adjournments or postponements thereof is January 12, 2018.Our Board recommends that stockholders voteFOR each of the director nominees nominated by our Board, andFOR Items 2, 3 and 4. After considering these items of business at the meeting, Dan Batrack, our Chairman and Chief Executive Officer, will review our fiscal 2017 performance and answer your questions.

Even if you cannot attend the Annual Meeting, it is important that your shares be represented and voted. You may vote as follows:

​  

By Telephone
On the Internet
By Mail
In Person

In the U.S. or Canada, you can vote your shares by calling 1.800.690.6903 before 11:59 p.m. Eastern Time on March 7, 2018.

You can vote your shares online atwww.proxyvote.com before 11:59 p.m. Eastern Time on March 7, 2018.

You can vote by mail by completing, dating and signing your proxy card and returning it in the postage-paid envelope provided or sending it to Vote Processing c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717.

You can vote in person at the Annual Meeting. Beneficial holders must contact their broker or other nominee if they wish to vote in person.

​ ​ ​ ​ ​ ​ ​ ​ 

On behalf of the Board of Directors, management, and employees of Tetra Tech, we thank you for your continued support.

By order of the Board of Directors,
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Preston Hopson
Senior Vice President, General Counsel, and Secretary
January 18, 2024
Pasadena, California
Important Notice about the Availability of Proxy Materials. The Notice of the 2024 Annual Meeting, proxy statement, and our 2023 Annual Report on Form 10-K are available at proxyvote.com. You are encouraged to access and review all the important information contained in our proxy materials before voting.


TABLE OF CONTENTS

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BY ORDER OF THE BOARD OF DIRECTORS42



Preston Hopson
Senior Vice President, General Counsel and Secretary
51

Pasadena, California
January 24, 2018


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Table

Special Note Regarding Forward-Looking Statements
Special Note Regarding Forward-Looking Statements
This proxy statement contains forward-looking statements regarding future events and our future results that are subject to the safe harbors created under the Securities Act of Contents

1933, as amended (Securities Act) and the Securities Exchange Act of 1934, as amended (Exchange Act). All statements other than statements of historical facts are statements that could be deemed forward-looking statements. These statements are based on current expectations, estimates, forecasts and projections about the industries in which we operate and the beliefs and assumptions of our management. Words such as “expects,” “anticipates,” “targets,” “goals,” “projects,” “intends,” “plans,” “believes,” “estimates,” “seeks,” “continues,” “may,” variations of such words and similar expressions are intended to identify such forward-looking statements. In addition, statements that refer to projections of our future financial performance, our anticipated growth and trends in our businesses and other characterizations of future events or circumstances are forward-looking statements. Readers are cautioned that these forward-looking statements are only predictions and are subject to risks, uncertainties and assumptions that are difficult to predict, including those discussed under “Part I—Item 1A. Risk Factors,” in our Annual Report on Form 10-K for the year ended October 1, 2023 and other U.S. Securities and Exchange Commission (SEC) filings, including future SEC filings. Therefore, actual results may differ materially and adversely from those expressed in any forward-looking statements. In particular, ESG goals included in this proxy statement are aspirational and do not constitute assurances that such goals will be achieved. Historical and forward-looking ESG-related statements may be based on standards that are still developing, internal Company controls and processes that continue to evolve, and assumptions that are subject to change. ESG-related figures and percentages in this report include estimates or approximations and may be based on assumptions or incomplete data.
All forward-looking statements are necessarily only estimates of future results, and there can be no assurance that actual results will not differ materially from our expectations. You are therefore cautioned not to place undue reliance on such statements. Any forward-looking statements are qualified in their entirety by reference to the risk factors discussed throughout the documents incorporated by reference in this proxy statement. Further, any forward-looking statement speaks only as of the date on which it is made, and we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which the statement is made or to reflect the occurrence of unanticipated events.
PROXY SUMMARY

Tetra Tech 2024 Proxy Statement 1

Proxy Summary
Proxy Summary
This section contains summary information describedexplained in greater detail in other parts of this proxy statement and does not contain all the information you should consider before voting. Stockholders are urged to read the entire proxy statement before voting.

TETRA TECH

On January 18, 2024, we intend to make our proxy materials, including this proxy statement, available to all stockholders entitled to vote at the 2024 Annual Meeting.

Tetra Tech
Tetra Tech is a leading global provider of high-end consulting and engineering services that focuses on water, environment, sustainable infrastructure, resource management,renewable energy, and international development. We are a global company that is renownedLeading with Science® to provide innovative solutions for our expertise in providing water-related solutions for public and private clients. We typically begin at the earliest stage of a project by identifying technical solutions and developing execution plans tailored to our clients’ needs and resources.
Engineering News-Record (ENR), the engineering industry’s leading trade journal for our industry,magazine, has ranked Tetra Tech as the number one water services firm#1 in Water for 14 consecutive20 years most recently in its May 2017 "Top 500 Design Firms" issue.a row. In 2017,2023, we were also ranked number one#1 in environmental management, hydro plants, water treatment/desalination, and water treatment and supply, environmental management,treatment/supply. ENR also ranked Tetra Tech in the top 10 in numerous categories, including dams and reservoirs, marine and port facilities, wind power, solar power, solid waste, and wind power. We were ranked among the 10 largest firms in numerous other services lines, including engineering/design, environmental science, chemical and soil remediation, green building design, hazardous waste, and site assessment and compliance, and hazardous waste.

              Our approach is to serve our clients byLeading with Science®, which differentiates us in the marketplace, and emphasizes innovation and investment in new and emerging technologies in growing our business. compliance.

Our reputation for high-end consulting and engineering expertise,services and our ability to apply our skills to develop innovative, sustainable solutions for our clients, haswater and environmental management have supported our growth for over 50more than 55 years. By combining ingenuity and practical experience, we have helped to advance solutions for managing water, protecting the environment, providing energy, and engineering the infrastructure for our cities and communities. Today, we are workingproud to be making a difference in people’s lives worldwide through our high-end consulting, engineering, and technology service offerings. In fiscal 2023 with a talent force of 27,000 employees, we worked on projects worldwide, and currently have more than 16,000 staff,100,000 projects in over 100 countries on all seven continents. We are Leading with Science® throughout our operations, with domain experts across multiple disciplines supported by our advanced analytics, artificial intelligence, machine learning, and over 400 offices.

ANNUAL MEETING INFORMATION

digital technology solutions. Our ability to provide innovation and first-of-a-kind solutions is enhanced by partnerships with our forward-thinking clients. We are diverse, equitable, and inclusive, embracing the breadth of experience across our talented workforce worldwide with a culture of innovation and entrepreneurship. We are disciplined in our business and focused on delivering value to customers and high performance for our stockholders. In supporting our clients, we seek to add value and provide long-term sustainable consulting, engineering, and technology solutions.
Items Being Voted on at the Annual Meeting
Stockholders will be asked to vote on the following items at the 2024 Annual Meeting:




Time And Date




10:00 a.m. Pacific Time on Thursday, March 8, 2018


Item




Place




Westin Pasadena, 191 N. Los Robles Avenue, Pasadena, California 91101


Board
Recommendation




Record Date




Stockholders as of the close of business on January 12, 2018






Attending the
Meeting




Please follow the instructions described under "Annual Meeting Procedures" in theMeeting and Voting Information section of this proxy statement


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ITEMS BEING VOTED ON AT ANNUAL MEETING

Vote RequiredDiscretionary
Broker Voting
Item 1. Election of directors
Item
Board
Recommendation


Vote Required
Discretionary
Broker Voting


FOR
each nominee
Majority of votes cast

No


1.


Election of directors




FOR
each nominee




Majority of votes cast




No





Item 2.


Advisory vote to approve named executive officers’ compensation



FOR

FOR




Majority of shares represented and entitled to vote on the item



No

No





Item 3.


Approval of the 2018 Equity Incentive Plan




FOR




Majority of shares represented and entitled to vote




No





4.


Ratification of appointment of PricewaterhouseCoopers LLP as independent registered public accounting firm for fiscal year 20182024



FOR

FOR




Majority of shares represented and entitled to vote




Yes


on the itemYes


Tetra Tech 2024 Proxy Statement 2

TABLE OF CONTENTS FISCAL 2017 PERFORMANCE HIGHLIGHTS

              Summary.

Proxy Summary
Fiscal Year 2023 Performance Highlights
Tetra Tech'sTech’s fiscal 2017year (FY) 2023 operating results reflected a significant improvementwere strong and demonstrated increased performance compared to fiscal 2016,FY 2022, which was itself a year of strong operational and financial performance, andperformance. In FY 2023 we achieved record-highs inrecord annual results, with all-time highs for revenue, operating income, adjusted EBITDA, earnings and diluted earnings per share (EPS).cash flow. Our focus on providing clients with high-endhigh end differentiated consulting and engineering services primarily in the water, environment and infrastructure markets, has resulted in increased margins and reduced risk in our business.

              Our fiscal 2017 revenue growth was generally consistent

We ended FY 2023 with our annual operating plan, and resulted from broad-based contract wins. The revenue growth was led by our U.S. federal government business, which increased 15% compared to fiscal 2016, and our U.S. state and local government business, which increased 14% compared to the prior year. We began fiscal 2018 withan authorized and funded backlog that reached ananother all-time high in the fourth quarter of fiscal 2017.

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approximately $4.8 billion.

Highlights of our fiscal 2017FY 2023 results of operations as reported in our fiscal year 2017FY 2023 Annual Report on Form 10-K are noted below:


Fiscal 2017in the table below.

FY 2023 Highlights

($ in millions, except EPS)

GRAPHIC

EPS and percentages)

$vs. FY 2022
Revenue$4,523+29%
Cash from Operations$368+10%
EPS$5.10+5%
Backlog$4,790+28%
Strong Stock Price Performance.Performance
Our strong annual total stockholder return (TSR) of 32% in fiscal 2017 (September 30, 2016 to September 29, 2017) contributed tofor our cumulative three-year TSR of 91% forwas 70% and our cumulative five-year TSR was 130%. TSR measures the fiscal 2015 through fiscal 2017 period (September 26, 2014 to September 29, 2017)return we have provided our stockholders, including stock price appreciation and dividends paid (assuming reinvestment thereof). We compare our TSR to the S&P 1000 and our TSR peer group (listed on p. 52page 51 of this proxy statement), and for purposes of our long-term incentive (LTI) program, as more fully explained below. We outperformed both in fiscal 2017 andmarket comparisons over the cumulative three-year period. Our three-year percentile vs. our TSR peer groupperiod and the S&P 1000 was 89% and 82%, respectively. TSR measures the return that we have provided our stockholders, including stock price appreciation and dividends paid (assuming reinvestment thereof).


One- and Three-Year TSR

five-year period.
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GRAPHICGRAPHIC
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Disciplined Capital Allocation.    Effectively deployingAllocation
Deploying capital effectively is one of our core strategies, and westrategies. We have been consistently disciplined in our execution of that strategy by returning cash to our stockholders through dividends and stock repurchases, while being a strategic and financially disciplined investor with respect to investing in our organic growth and strategic acquisitions. Over the last three years, we have returned $360$398 million to stockholders.

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Return of Cash to Stockholders

GRAPHIC

CORPORATE GOVERNANCE HIGHLIGHTS

stockholders through dividends and stock repurchases.

Corporate Governance Highlights
Our corporate governance policies and practices reflect our values,principles (discussed in the Corporate Governance, Sustainability, and Social Responsibility section on page 8 of this proxy statement) and allow our Board to effectively oversee our companyCompany in the interest of creating long-term value. The key elements of our program and the related benefits to our stockholders are set forth below:

in the following table.

Tetra Tech 2024 Proxy Statement 3

Proxy Summary
Corporate Governance Key Elements



Our Practice or Policy





Description and Benefit to Our Stockholders



​ ​ ​ ​ 
STOCKHOLDER RIGHTS
Stockholder Rights
​  Annual Election of DirectorsOur directors are elected annually, reinforcing their accountability to our stockholders.
​ ​ 
​  Single Class of Outstanding Voting StockWe have no class of preferred stock outstanding, which means that our common stockholders together control our company with equal voting rights.
​ ​ 
​  Majority Voting for Director ElectionsWe have a majority vote standard for uncontested director elections, which increases Board accountability to stockholders.
​ ​ 
​  Mandatory Director Resignation PolicyIncumbent directors who receive more "AGAINST" votes than "FOR" votes must tender their resignation to the Board for consideration.
​ ​ 
​  No Poison PillWe do not have a stockholder rights plan (commonly referred to as a "poison pill").
​ ​ 
​  Stockholder Calls for Special MeetingsOur bylaws allow stockholders owning 20% or more of our outstanding shares to call a special meeting of stockholders.
StructureExecutive Compensation

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Our Practice or Policy





Description and Benefit to Our Stockholders




Annual Election of Directors

Single Class of Voting Stock

Majority Voting for Director Elections

Mandatory Director Resignation Policy

No Poison Pill

Stockholder Calls for Special Meetings

Stockholder Action by Written Consent

Majority Voting for Charter Amendments
BOARD STRUCTURE

Proxy Access

~90% Independent Directors
​  Governance PoliciesOur Corporate Governance Policies provide stockholders

Director Diversity with information regarding the best practice principles of our corporate governance program and Board framework.
50% Female Representation
​ ​ 
​  90% IndependentAll of our current directors, except our Chairman/Chief Executive Officer (CEO), are independent, ensuring that our directors oversee our company without undue influence from management.
​ ​ 
​  

Robust Presiding Director Role
Our Presiding Director is selected by our independent directors for a four-year term to perform clearly delineated duties, such as presiding

Term Limits and Mandatory Retirement

Board Refreshment

Annual Evaluations

Executive Sessions at executive sessions of our Board and serving as the principal liaison between the independent directors and the CEO.
​ ​ 
​  Committee GovernanceMeetings
Our Board Committees have written charters that clearly establish their respective roles and responsibilities, and are comprised exclusively of independent directors. Committee composition and charters are reviewed annually by our Board.
​ ​ 
​  Mandatory RetirementWe have adopted a mandatory director retirement age of 75, which helps ensure regular refreshment of our Board. However, Mr. Grant has been exempted because of his special qualifications and experience, and the Board has waived this mandatory retirement requirement solely for him.
​ ​ 
​  Board RefreshmentOur Board's Nominating and Corporate Governance (NCG) Committee annually reviews our Board composition, which helps ensure we have the right balance between continuity and fresh perspectives. We added three new directors over the last four years and one long-serving director retired, thereby reducing the average tenure of the Board.
​ ​ 
​  Annual Performance EvaluationsOur NCG Committee oversees an annual performance evaluation of our Board, and its Committees and leadership, to ensure they continue to serve the best interests of stockholders.
​ ​ 
​  

Access to Management and Experts
Our Board and Committees have complete access to all levels of management and can engage advisors at our expense, giving them access to employees with direct responsibility for managing our company and experts to help them fulfill their oversight responsibilities on behalf of our stockholders.
​ ​ 
​  

Succession Planning
Our Board's NCG Committee and/or our full Board reviews potential for CEO and other senior executive successors annually to develop our future leaders and ensure we can sustain business continuity.
Leadership
EXECUTIVE COMPENSATION
​  

At-Risk, Performance-Based Compensation
For fiscal 2017, 82% of our CEO's target total direct compensation (TDC),

Environmental, Social, and an average of 64% of our other Named Executive Officers' (NEOs') target TDC, was at-risk (all compensation components other than base salary). Further, 67% of our CEO's target TDC, and an average of 54% of our other NEOs' target TDC, was performance-based (annual incentive plan (AIP) award, options and performance share units (PSUs)).
Governance (ESG) Factors
​ ​ 
​  

Annual Say-on-PaySay-On-Pay Vote
Stockholders have the opportunity annually to cast an advisory vote on our executive compensation.
​ ​ 
​  

Executive and Director Stock Ownership Guidelines

Compensation Committee of All of our directors (other than Ms. Maguire who joinedIndependent Directors

Independent Compensation Consultant to the Board in November 2016) and executive officers have met our stock ownership guidelines, helping ensure the alignment of their interests with those of our stockholders.
Committee
​ ​ 
​  

Best Practices
Our executive compensation program reflects a number of best practices that are summarized at the end of this proxy summary and in the executive summary of theCompensation Discussion and Analysis section of our proxy statement.

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2018 DIRECTOR NOMINEES

2024 Director Nominees
Our Board has overseen the continuing transformation of our company,Company, including our strategic decision to focus on our high-end consulting and engineering business. Further, the Board has overseen the continuation of our capital allocation plan, which included share repurchases of $100 million and cash dividends of $22$52 million in fiscal 2017.FY 2023. Our Board members have demonstrated their commitment to diligently and effectively executing their fiduciary duties on behalf of our stockholders, and we recommend that each of our incumbent directors (introduced in the following currently serving directorstable below) be re-electedreelected at the 2024 Annual Meeting, with the exception of Mr. Thompson, who will retire at the 2024 Annual Meeting.


Tetra Tech 2024 Proxy Statement 4

Proxy Summary

 

 

Name


 Age
 Director
Since


 Principal Occupation
 Independent
 AC
 CC
 GC
 SC

 

 

Dan L. Batrack

   59   2005   Chairman and CEO, Tetra Tech, Inc.   No                  

 

 

Hugh M. Grant

   81   2003   Retired Vice Chair & Regional Managing Partner, Ernst & Young LLP   Yes   C       M      

 

 

Patrick C. Haden

   64   1992   President, Wilson Avenue Consulting   Yes       M   M      

 

 

J. Christopher Lewis

   61   1988   Managing Director, Riordan, Lewis & Haden   Yes   M   M          

 

 

Joanne M. Maguire

   63   2016   Retired Executive Vice President, Lockheed Martin Space Systems Company   Yes           C   M  

 

 

Kimberly E. Ritrievi

   59   2013   President, The Ritrievi Group LLC   Yes   M           M  

 

 

Albert E. Smith (PD)

   68   2005   Retired Executive Vice President, Lockheed Martin   Yes           M   C  

 

 

J. Kenneth Thompson

   66   2007   President and CEO, Pacific Star Energy, LLC   Yes       C       M  

 

 

Kirsten M. Volpi

   53   2013   EVP for Finance and Administration, COO, CFO and Treasurer, Colorado School of Mines   Yes   M   M          
2024 Director Nominees

AC = Audit Committee         CC = Compensation Committee         GC = Nominating and Corporate Governance Committee
SC = Strategic Planning and Enterprise Risk Committee         M = Member         C = Chair         PD = Presiding Director

NameAgeDirector SincePrincipal OccupationIndependentACCCNCSC
Dan L. Batrack652005Chairman and Chief Executive Officer (CEO), Tetra Tech
Gary R. Birkenbeuel662018Retired Regional Assurance Managing Partner, Ernst & Young LLPC
Prashant Gandhi522022Chief Business Officer, Melio Payments
Joanne M. Maguire*692016Retired Executive Vice President (EVP), Lockheed Martin SpaceC
Christiana Obiaya412023Chief Executive Officer, Heliogen
Kimberly E. Ritrievi652013President, The Ritrievi Group LLCC
Kirsten M. Volpi592013EVP, Chief Operating Officer, and Chief Financial Officer, Colorado School of MinesC**
Meetings Held4433
Notes:
AC = Audit Committee
CC = Compensation Committee
NC = Nominating and Corporate Governance Committee
SC = Strategic Planning and Enterprise Risk Committee
C = Committee Chair
* = Presiding Director
** =
Ms. Volpi will become Chair of the Compensation Committee upon Mr. Thompson’s retirement.

Tetra Tech 2024 Proxy Statement 5

Proxy Summary
GRAPHICGRAPHIC
[MISSING IMAGE: pc_directornominees-pn.jpg]

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EXECUTIVE COMPENSATION HIGHLIGHTS

Executive Compensation Highlights
Our Board'sBoard’s Compensation Committee designs our executive compensation program to motivate our executives to executeimplement our business strategies and deliver long-term stockholder value. We pay for performance with compensation dependent on our achieving financial, share price, and business performance objectives, that advancewhile aligning executives with the long-term interests of our stockholders.

              We value our stockholders' opinions about our governance The following graphic illustrates the annual and compensation practices, and we actively solicit input through our stockholder outreach program. In advancelong-term components of the 2018 Annual Meeting, we engaged in telephonic, email and/or in-person discussions with stockholders representing more than 50% of our outstanding shares.

              The TDC paid to our executives is comprised of the following three components:

executive compensation.
Base salary;

Performance-based cash incentive under our AIP; and

Long-term incentives (LTIs) delivered in equity and consisting of:

50% PSUs with cliff vesting after a three-year performance period, subject to achievement of the applicable performance goals, based 50% on EPS growth and 50% on relative TSR,

25% stock options vesting over four years, subject to the holder's continuous employment by us through the applicable vesting date, and

25% restricted stock units (RSUs) vesting over four years, subject to the holder's continuous employment by us through the applicable vesting date.

Tetra Tech 2024 Proxy Statement 6


TABLE OF CONTENTS
Fiscal 2017 Elements
Proxy Summary
FY 2023 Components of Annual and Long-Term Compensation

GRAPHIC

              We structure the TDC of our Named Executive Officers (NEOs) so that it results in payments that approximate the market median, giving consideration to various factors, including: responsibilities, individual performance, tenure, retention, company performance, succession planning and competitive market levels. The majority of this compensation is tied to financial, operational or stock price performance and is therefore "at risk", meaning that if we fail to achieve our financial objectives and create stockholder value, our executives may ultimately not realize some or all of the performance-based

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components of compensation and result in payments below the market median. In fiscal 2017, 82% of our CEO's target TDC, and an average of 64% of our other NEOs' target TDC, was at-risk (all compensation components other than base salary). Further, 67% of our CEO's target TDC, and an average of 54% of our other NEOs' target TDC, was performance-based (AIP award, options and PSUs).


Fiscal 2017 Target Total Direct Compensation Mix*

[MISSING IMAGE: pc_annual-pn.jpg]
GRAPHICGRAPHIC
*
See theCompensation Discussion and Analysis section of this proxy statement for a description of the manner in which these amounts are determined.

Pay for Performance

              Our Compensation Committee designed the executive compensation program to reflect its philosophy that a majority of compensation should be tied to our success in meeting predetermined performance objectives, the achievement of which should positively influence our stock price. The objective is to motivate the executives to achieve these annual and long-term financial goals in order to deliver a consistent and sustainable return to our stockholders. As indicated below, for the period from fiscal 2014 to 2017, our CEO reported compensation increased 20% and, on average, our other NEOs reported compensation increased 27%, compared to the 91% increase in our TSR performance over the same period. See theCompensation Discussion and Analysis and the Summary Compensation Table in this proxy statement for additional information.

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Change in Reported Compensation Compared to Three-Year Cumulative TSR
Fiscal 2014 to Fiscal 2017

GRAPHIC

Compensation Best Practices

As summarized below and described in further detail in theCompensation Discussion and Analysis section on page 37 of this proxy statement, our executive compensation program is aligned with our goals and strategies and reflects what we believe are best practices.

What We Do
[MISSING IMAGE: ic_tick-pn.gif]
Focus on pay for performance: In FY 2023, 87% of our Chief Executive Officer’s (CEO’s) target total direct compensation (TDC) and an average of 71% of our other named executive officers’ (NEOs’) target TDC was at-risk; and 60% of our CEO’s target TDC and an average of 52% of our other NEOs’ target TDC was tied to Company performance
[MISSING IMAGE: ic_tick-pn.gif]
Review the Compensation Committee’s charter, and evaluate the Compensation Committee’s performance
[MISSING IMAGE: ic_tick-pn.gif]
Emphasize long-term performance: In FY 2023, 67% of our CEO’s target TDC and an average of 48% of our other NEOs’ target TDC was equity based and, thereby, tied to creating stockholder value
[MISSING IMAGE: ic_tick-pn.gif]
Use an independent compensation consultant retained directly by the Compensation Committee
[MISSING IMAGE: ic_tick-pn.gif]
Require double trigger for change in control equity vesting and cash severance benefits
[MISSING IMAGE: ic_tick-pn.gif]
Assess potential risks relating to our compensation policies and practices
[MISSING IMAGE: ic_tick-pn.gif]
Maintain stock ownership guidelines for both executives and the Board of Directors
[MISSING IMAGE: ic_tick-pn.gif]
Maintain a clawback policy

What We Do


Tetra Tech 2024 Proxy Statement 7

Pay for performance: in fiscal 2017, 82% of our CEO's target TDC, and an average of 64% of our other NEOs' target TDC, was at-risk; and 67% of our CEO's target TDC, and an average of 54% of our other NEOs' target TDC, was tied to company performance
Proxy Summary
What We Do Not Do
[MISSING IMAGE: ic_donot-pn.gif]
Have employment agreements with our NEOs
[MISSING IMAGE: ic_donot-pn.gif]
Grant stock options with an exercise price less than the fair market value on the date of grant
[MISSING IMAGE: ic_donot-pn.gif]
Provide excise tax gross up payments in connection with change in control severance benefits
[MISSING IMAGE: ic_donot-pn.gif]
Reprice or exchange stock options
[MISSING IMAGE: ic_donot-pn.gif]
Provide gross ups to cover tax liabilities associated with executive perquisites
[MISSING IMAGE: ic_donot-pn.gif]
Promise multiyear guarantees for bonus payouts or salary increases
[MISSING IMAGE: ic_donot-pn.gif]
Permit directors, officers, or employees to hedge or pledge Company stock
[MISSING IMAGE: ic_donot-pn.gif]
Pay dividends or dividend equivalents on equity awards unless and until the awards vest
FY 2023 Target Total Direct Compensation Mix1
[MISSING IMAGE: pc_ceoneo-pn.jpg]
Emphasize long-term performance: in fiscal 2017, 61% of our CEO's target TDC, and an average of 40% of our other NEOs' target TDC, was equity-based and thereby tied to creating stockholder value
Use double-trigger change in control vesting provisions: vesting of equity following a change in control requires a qualifying termination of employment within two years
Maintain stock ownership guidelines for both executives and the Board of Directors
Maintain a clawback policy
Use an independent compensation consultant retained directly by1 See the Compensation Committee
Discussion and Analysis section on page 37 of this proxy statement for a description of how these amounts are determined.
Regularly assess potential risks relating to our compensation policies and practices
Ratification of Appointment of PricewaterhouseCoopers LLP
Annually review the Compensation Committee's charter and evaluate the Compensation Committee's performance

What We Don't Do

X
Have employment agreements with our NEOs
X
Excise tax gross up payments in connection with change in control severance benefits
X
Provide gross-ups to cover tax liabilities associated with executive perquisites
X
Permit directors or officers to hedge or pledge company stock
X
Grant stock options with an exercise price less than the fair market value on the date of grant
X
Re-price or exchange stock options without stockholder approval
X
Promise multi-year guarantees for bonus payouts or salary increases
X
Pay accrued dividend equivalents unless and until the underlying equity awards vest

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APPROVAL OF THE 2018 EQUITY INCENTIVE PLAN

              We last sought shareholder approval of a new equity incentive plan in 2015. We are seeking approval and adoption of the Tetra Tech, Inc. 2018 Equity Incentive Plan (2018 Plan), which provides for the grant of stock options (including non-qualified and incentive stock options, SARs, restricted stock, restricted stock units (RSUs), stock bonus awards, dividend equivalents and performance compensation awards (including, but not limited to, performance stock units (PSUs)). The purpose of the 2018 Plan is to promote the interests of the company and our stockholders by enabling us to offer our employees, directors, consultants and advisors an opportunity to acquire an equity interest in the company so as to better attract, retain, and reward our service providers and, accordingly, to strengthen the mutuality of interests between participants in the 2018 Plan and our stockholders by providing such participants with a proprietary interest in pursuing our long-term growth and financial success. Our Board unanimously determined that the 2018 Plan is in the best interests of our company and its stockholders.

RATIFICATION OF APPOINTMENT OF PWC

              Our Board'sBoard’s Audit Committee has appointed PricewaterhouseCoopers LLP (PwC) as our independent registered public accounting firm for the 20182024 fiscal year, and our Board is seeking stockholder ratification of the appointment. PwC is knowledgeable about our operations and accounting practices and is well qualified to act as our independent registered public accounting firm. The Audit Committee considered the qualifications, performance, and independence of PwC,PwC; the quality of its discussions with PwC,PwC; and the fees charged by PwC for the level and quality of services provided during fiscal 2017,FY 2023 and has determined that the reappointment of PwC is in the best interest of our companyCompany and itsour stockholders.

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PROXY STATEMENT FOR TETRA TECH, INC.
2018 ANNUAL MEETING OF STOCKHOLDERS


Tetra Tech 2024 Proxy Statement 8

Corporate Governance, Sustainability, and Social Responsibility
Corporate Governance, Sustainability, and Social Responsibility
Tetra Tech’s Mission, Purpose, and Core Principles
Our Mission: To be the premier worldwide high-end consulting and engineering firm, focusing on water, environment,
and sustainable infrastructure.

PROXY SUMMARY

Core Principles
Our core principles form the underpinning of how we work together to serve our clients.

Service: Tetra Tech puts our clients first. We listen to better understand our clients’ needs and deliver smart, cost-effective solutions that meet those needs.

Value: Tetra Tech takes on our clients’ problems as if they were our own. We develop and implement innovative solutions that are cost effective, efficient, and practical.

Excellence: Tetra Tech brings superior technical capability, disciplined project management, and excellence in safety and quality to all our work.

Opportunity: Our people are our number one asset. Our workforce is diverse and includes leading experts in our fields. Our entrepreneurial nature and commitment to success provide challenges and opportunities for all our employees.
i

TETRA TECH

i

ANNUAL MEETING INFORMATION

Purpose
Tetra Tech will enhance the quality of life while creating value for customers, employees, investors, and partners.
i

ITEMS BEING VOTED ON AT ANNUAL MEETING

ii

FISCAL 2017 PERFORMANCE HIGHLIGHTS

ii

CORPORATE GOVERNANCE HIGHLIGHTS

iv

2018 DIRECTOR NOMINEES

vi

EXECUTIVE COMPENSATION HIGHLIGHTS

vii

APPROVAL OF THE 2018 EQUITY INCENTIVE PLAN

x

RATIFICATION OF APPOINTMENT OF PWC

x

CORPORATE GOVERNANCE, SUSTAINABILITY AND CORPORATE SOCIAL RESPONSIBILITY


1

CORPORATE GOVERNANCE

1

SUSTAINABILITY

2

CORPORATE SOCIAL RESPONSIBILITY

3

OUR BOARD OF DIRECTORS


4

OVERVIEW

4

BOARD COMPOSITION

4

BOARD MEETINGS AND ATTENDANCE

5

CORPORATE GOVERNANCE POLICIES

5

DIRECTOR INDEPENDENCE

6

BOARD LEADERSHIP STRUCTURE

7

BOARD COMMITTEES

8

EXECUTIVE SESSIONS

12

RISK OVERSIGHT

12

SUCCESSION PLANNING

15

BOARD AND COMMITTEE EVALUATIONS

15

ACTIVE STOCKHOLDER ENGAGEMENT AND COMMUNICATIONS POLICY

15

ITEM 1 – ELECTION OF DIRECTORS


17

MAJORITY VOTING STANDARD

17

RECOMMENDATION OF BOARD OF DIRECTORS

17

SELECTION OF DIRECTOR NOMINEES

17

STOCKHOLDER SUBMISSION OF DIRECTOR NOMINEES

18

DIRECTOR QUALIFICATIONS

19

BOARD REFRESHMENT

20

DIRECTOR DIVERSITY

21

2018 DIRECTOR NOMINEES

21

DIRECTOR COMPENSATION

31

ITEM 2 – ADVISORY VOTE TO APPROVE EXECUTIVE COMPENSATION


35

RECOMMENDATION OF BOARD OF DIRECTORS

35

MEANING OF ADVISORY VOTE

35

COMPENSATION DISCUSSION AND ANALYSIS


36

EXECUTIVE SUMMARY

36

STRONG COMPENSATION GOVERNANCE PRACTICES

39

2017 SAY ON PAY VOTE AND EXECUTIVE COMPENSATION PROGRAM

40

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Corporate Governance

OVERVIEW OF PAY PHILOSOPHY AND EXECUTIVE COMPENSATION COMPONENTS

41

SUMMARY OF COMPENSATION DECISIONS FOR FISCAL 2017

43

ASSESSMENT OF PAY FOR PERFORMANCE

46

DISCUSSION OF COMPENSATION COMPONENTS AND DECISIONS IMPACTING FISCAL 2017 COMPENSATION

46

OTHER BENEFITS

57

TERMINATION AND CHANGE IN CONTROL

57

COMPENSATION-SETTING PROCESS AND TOOLS

58

INDEPENDENT OVERSIGHT AND EXPERTISE

59

ADVISOR INDEPENDENCE

59

STOCK OWNERSHIP GUIDELINES

60

CLAWBACK POLICY

61

TAX IMPLICATIONS OF EXECUTIVE COMPENSATION

61

COMPENSATION COMMITTEE REPORT


63

COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION

63

EXECUTIVE COMPENSATION TABLES


64

SUMMARY COMPENSATION TABLE

64

GRANTS OF PLAN-BASED AWARDS – FISCAL 2017

66

OUTSTANDING EQUITY AWARDS AT FISCAL YEAR-END – FISCAL 2017

68

OPTIONS EXERCISED AND STOCK VESTED – FISCAL 2017

70

NONQUALIFIED DEFERRED COMPENSATION – FISCAL 2017

70

POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

71

EQUITY COMPENSATION PLAN INFORMATION

79

ITEM 3 – APPROVAL OF THE 2018 EQUITY INCENTIVE PLAN


80

DESCRIPTION OF THE 2018 PLAN

80

U.S. TAX CONSEQUENCES UNDER THE 2018 PLAN

87

KEY METRICS RELATED TO THE EXISTING PLAN

89

NEW PLAN BENEFITS

90

RECOMMENDATION OF THE BOARD OF DIRECTORS

90

ITEM 4 – RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM


91

RECOMMENDATION OF THE BOARD OF DIRECTORS

91

AUDITOR INDEPENDENCE

92

AUDITOR FEES

92

POLICY ON AUDIT COMMITTEE PRE-APPROVAL OF AUDIT AND PERMISSIBLE NON-AUDIT SERVICES

92

AUDIT COMMITTEE REPORT


93

SECURITY OWNERSHIP INFORMATION


94

INSIDER TRADING POLICY; PROHIBITION ON HEDGING AND PLEDGING

94

SECURITY OWNERSHIP OF MANAGEMENT AND SIGNIFICANT STOCKHOLDERS

94

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

95

RELATED PERSON TRANSACTIONS

96

MEETING AND VOTING INFORMATION


98

DELIVERY OF ANNUAL REPORT ON FORM 10-K

98

DELIVERY OF PROXY MATERIALS

98

HOUSEHOLDING

98

SHARES ENTITLED TO VOTE

99

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VOTING YOUR SHARES

99

REVOKING YOUR PROXY OR CHANGING YOUR VOTE

100

CONFIDENTIALITY OF YOUR VOTE

100

QUORUM AND VOTES REQUIRED

100

VOTING ON ADDITIONAL BUSINESS

101

VOTE RESULTS

101

PROXY SOLICITATION

101

ELECTRONIC ACCESS TO PROXY MATERIALS AND ANNUAL REPORT

101

TIME AND LOCATION OF ANNUAL MEETING

102

ANNUAL MEETING PROCEDURES

102

SUBMISSION OF STOCKHOLDER ITEMS FOR 2019 ANNUAL MEETING

102

OTHER MATTERS

103

APPENDIX A 2018 EQUITY INCENTIVE PLAN


A-1

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CORPORATE GOVERNANCE, SUSTAINABILITY AND
CORPORATE SOCIAL RESPONSIBILITY

              Our mission is to be the premier worldwide consulting and engineering firm, focusing on water, environment, infrastructure, resource management, energy and international development services. We are renowned for our expertise in providing water-related solutions for public and private clients. We typically begin at the earliest stage of a project by identifying technical solutions and developing execution plans tailored to our clients' needs and resources. Our solutions may span the entire life cycle of consulting and engineering projects.

              Our reputation for high-end consulting and engineering expertise and our ability to apply our skills to develop innovative solutions for our clients has supported our growth over 50 years. By combining ingenuity and practical experience, we have helped to advance solutions for managing water, protecting the environment, providing energy, and engineering the infrastructure for our cities and communities.

CORPORATE GOVERNANCE

Under the oversight of our Board of Directors, we have designed our corporate governance programCorporate Governance Program to ensure continued compliance with applicable laws and regulations, the rules of the Securities and Exchange Commission (SEC), and the listing standards of the Nasdaq Stock Market (Nasdaq),; and to reflect best practices as informed by the recommendations of our outside advisors, the voting guidelines of our stockholders, the policies of proxy advisory firms, and the policies of other public companies.

We are committed to operating with honesty and integrity and maintaining the highest level of ethical conduct. We encourage stockholders to visit the Corporate Governance section ofon our website at investor.tetratech.com/esg/governance-overview, which includes the following corporate governance documents:


Corporate Code of Business Conduct;

Conduct

Finance Code of Professional Conduct, which applies to our CEOChief Executive Officer (CEO) and all members of our finance department, including our chief financial officerChief Financial Officer (CFO) and principal accounting officer;

Chief Accounting Officer (CAO)

Corporate Governance Policies;

Policies (see page 16 of this proxy statement for more detail on our Corporate Governance policies)

Charters for our Board'sBoard’s Audit Committee, Compensation Committee, NCGNominating and Corporate Governance (NCG) Committee, and Strategic Planning and Enterprise Risk Committee; and

(SPER) Committee

Stock Ownership Guidelines.

              You can access these documents by going to our website atwww.tetratech.com/en/corporate-governance, but should note that informationGuidelines

Information on our website is not and should not be considered part of, nor is it incorporated by reference into, this proxy statement. You can also receive copies of these documents, without charge, by written request mailed to our Corporate Secretary at Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107.

We maintain a 24-hour hotline that is available to all employees for the anonymous, confidential submission of employee, complaints.whistleblower and other complaints or concerns by telephone and internet. The hotline is operated by Navex Global, an independent third-party provider. All complaints go directly to our General Counsel and Chief Compliance Officer, and all complaints relating to accounting, internal controls, or auditing matters also go directly to the ChairmanChair of our Audit Committee; our General Counsel and Chief Compliance Officer provides regular reports on these complaints to the Audit Committee. We also maintain an internal audit control function that provides critical oversight over the key areas of our business and financial processes and controls and reports directly to the Audit

Tetra Tech 2024 Proxy Statement 9

TABLE OF CONTENTS
Corporate Governance, Sustainability, and Social Responsibility
Committee. Our Board


Table of Contents

has also adopted a written related“related person transactionstransactions” policy. Under the policy, the Audit Committee (or other committee designated by the NCG Committee) reviews transactions between usTetra Tech and "related“related persons."

              Our company” Tetra Tech had no related person transactions in FY 2023.

Tetra Tech conducts itsour business on the basesbasis of the quality of itsour services and the integrity of itsour association with itsour clients and others. Our Corporate Code of Conduct demonstrates our commitment to ascribe toupholding the highest standards of ethical conduct in the pursuit of our business and applies to all of our directors, officers, and employees. It hasWe require all directors, officers, and employees, and where necessary and appropriate, suppliers, contractors, and other business partners acting on our behalf, to complete periodic Code of Conduct trainings. Our policies have been translated into five languages, and our employees are trained on it and affirm their commitment to complycomplying with itthe policies when they first join our companyCompany and periodicallyregularly thereafter.

SUSTAINABILITY

Corporate Sustainability
Tetra Tech supports clients in more than 100 countries around the world, helping them to solve complex problems and achieve solutions that are technically socially and economically sustainable.advanced. Our high-end consulting and engineering services focus on using innovative technologies and creative solutions to minimize environmental impacts.impacts and enhance social systems. Our greatest contribution toward sustainability is through the projects we perform every day for our clients. Sustainability is embeddedclients, including water reuse programs, decarbonization of buildings, ecosystem restoration, and renewable energy transformation. In developing countries, we also support social programs such as gender equality programs, and enhancement of sustainable aquaculture and forestry economies. As a signatory of the United Nations Global Compact (UNGC) on human rights, labor, environment, and anti-corruption, Tetra Tech embraces the UNGC Ten Principles as part of the strategy, culture, and daily operations of our Company.
We actively engage with our stakeholders, internally and externally, to encourage input on the materiality of various ESG issues to Tetra Tech and incorporate input into our strategic planning and sustainability reporting. Our annual sustainability reporting and key metrics are aligned with the priorities we have set on human capital, professional development, health & safety, and ethics. We report on human capital metrics, including gender balance, racial and ethnic diversity in our projects – from recycling freshwater supplies to recycling water products, reducing energy consumption,workforce, employee engagement and reducing greenhouse gas emissions in developing countries.

              Our Sustainability Program focuses on supporting our mission to be a premier provider of consulting and engineering services focused on water, natural resources, environment, infrastructure, energy, and internationalprofessional development. We seek to achieve this mission by adopting a sustainability goal of "embracinghave supplier programs that integrate and emphasize sustainability in our businessthe procurement of goods and operations while supporting the company in delivering excellent services to our clients, maintaining superior financial performance, and emphasizing safety in the execution of services."

              Our Sustainability Program allows us to further expand our commitment to sustainability by encouraging, coordinating and reporting on actions to minimize our collective impacts on the environment. The Program has three primary pillars: Projects – the solutions we providesubcontracting for our clients; Procurement –projects. We have reported annually on GHG emissions for more than a decade, significantly reducing our procurementemissions from program inception. In 2021, we expanded our reporting and subcontracting approaches;set new goals for scope 1, 2, and Processes –3 emissions. The SBTi has approved Tetra Tech’s near-term science-based emissions reduction target. Based on input from stakeholders and in recognition of the internal policies and processesimportance of the project work we perform each year, in 2021 we also initiated our Billion People Challenge, with the overarching goal to improve the lives of one billion people by 2030. The Billion People Challenge progress is calculated each year based on our annual project impact analysis which evaluates five key metrics that promote sustainable practices, reduce costs and minimize environmental impacts. In addition, our program is based onare closely aligned with the Global Reporting Initiative (GRI)standards and the UN Sustainable Development Goals.

Billion People Challenge Baseline and Goals
MeasureSDGRelated GRI
Performance
Indicator
2022 AdditionsCumulative
from Baseline
2030 Goal
Lives ImprovedSDG 3, 4, 5, 16GRI 412-2138 million people
[MISSING IMAGE: ic_leaf-bw.jpg]
545 million people1 billion people
Project Metrics
WaterSDG 6GRI 303-2; GRI 303-3502 billion
gallons/year
[MISSING IMAGE: ic_leaf-bw.jpg][MISSING IMAGE: ic_roundtick-bw.jpg]589 billion
gallons
203.4 billion gallons of water treated, saved, or reused
Renewable EnergySDG 7GRI 302-2; GRI 302-3;
GRI 302-4; GRI 302-5
1,023
MW/year
[MISSING IMAGE: ic_leaf-bw.jpg]
17,800 MW36,800 MW of renewable energy identified, planned, or generated
EcosystemsSDG 14, 15GRI 304-2; GRI 304-36.7 million
ha/year
[MISSING IMAGE: ic_leaf-bw.jpg]
185 million ha320 million ha of land and water protected, managed, or restored
GHG Emission ReductionSDG 13GRI 305-2; GRI 305-3;
GRI 305-4; GRI 305-5
80.6 million
MT CO
2e/year
[MISSING IMAGE: ic_leaf-bw.jpg]
101.2 million MT CO2e
10% increase from baseline annually

Tetra Tech 2024 Proxy Statement 10

TABLE OF CONTENTS
Corporate Governance, Sustainability, and Social Responsibility
MeasureSDGRelated GRI
Performance
Indicator
2022 AdditionsCumulative
from Baseline
2030 Goal
Social and GovernanceSDG 3, 4, 5, 16GRI 412-332.2 million
people
[MISSING IMAGE: ic_leaf-bw.jpg]
70.7 million people20% increase from baseline
[MISSING IMAGE: ic_leaf-bw.jpg] Improvement from 2021    [MISSING IMAGE: ic_roundtick-bw.jpg] 2030 target achieved
Operational GHG Results and Goals
MeasureRelated GRI
Performance
Indicator
2022 Results
Change from 20212
2030 Goal
GHG Emissions from Operations1
GRI 305-1;
GRI 305-2;
GRI 305-3;
GRI 305-4;
GRI 305-5
2.08 MT CO2e per employee
1.06 MT CO2e Scope 1 and 2 per employee
48,188 MT CO2e (all employees)
Scope 1: 9,418 MT CO2e
Scope 2: 15,204 MT CO2e
Scope 3: 23,566 MT CO2e
25% decrease per employee (Scope 1 and 2)3
16% decrease all employees (Scope 1 and 2)3
[MISSING IMAGE: ic_leaf-bw.jpg]
[MISSING IMAGE: ic_leaf-bw.jpg]
50% reduction in GHG emissions from 2021 baseline
1 Global Warming Potentials for CO2e calculations are from IPCC Sixth Assessment Report, Framework, the internationally predominant sustainability2021 (AR6)
2 Year-on-year emissions normalized due to acquisitions and additional Scope 3 components
3 Due to continued expansion of Scope 3 reporting, protocol for corporate sustainability plans. The GRI includes three fundamental impact areas: environmental, economic, and social sustainability.

year-on-year comparison not applicable

Our Sustainability Program is led by our Chief Sustainability Officer, who has been appointed by executive managementour Board of Directors and is supported by other key corporate and operations representatives viathrough our Sustainability Council. We have established specific metrics forcontinuously review sustainability-related policies and practices, integrate input from stakeholders, and assess the company and six corporate service departments. In additionresults of our efforts in order to measuring our performance against these established metrics, we compile best practices from our operations and corporate service groups by meansmake future improvements. Tetra Tech’s Board of a quarterly sustainability survey. This survey is used to identify sustainable practices that can be introduced across the company. We compile best practices from our operations and corporate service groups by means of a sustainability survey. This survey is used to identify sustainable practices that can be transferred enterprise-wide and used to assess participation in our Sustainability Program.

              Our executive management team reviews and approvesDirectors’ SPER Committee oversees the Sustainability Program and evaluates our progress in achieving the goals and objectives outlined in our plan. Additional informationAs part of our membership in the UNGC, we annually report on ourthe Communication on Progress using Tetra Tech’s Sustainability Program and our annual sustainability report that documents our progress may be found on our website athttp://www.tetratech.com/en/sustainability.

Report.

Corporate Social Responsibility

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CORPORATE SOCIAL RESPONSIBILITY

              Our company

Tetra Tech seeks clear, sustainable solutions that improve the quality of life. We take this responsibility seriously because our work often places us at the center of our clients' environmental, safety and sustainability challenges. These challenges often involve the opinions of public, industry and government stakeholders who seek our advice on complex issues. We have helped thousands of towns, cities, industries and governments find sustainable solutions to complex issues concerning resource management and infrastructure.

              To provide solutions to these challenges, we believe in maintaining our technical objectivity. We have earned our reputationlife for technical objectivity over more than five decades. We have designed progressive, green buildings in New York City, helped the U.S. Department of Defense with pollution prevention and clean-up, and helped many Fortune 500 companies balance environmental needs with business goals. Weeveryone.

Our professionals are helping Vancouver achieve its goal of becoming the greenest city in the world. Tetra Tech companies hold memberships with the U.S. Green Building Council and the Chicago Climate Exchange.

              We also encourage our professionalsencouraged to participate in outreach programs to help improve the communities in which they live and work. Tetra Tech associatesemployees and offices around the globe participate in many financial, in-kind,in kind, volunteer, and pro bono activities each year. In 2016,2023 we advanced our commitment toLeading with Science® by launching through our Science, Technology, Engineering, and Mathematics (STEM) Program to help shape the next generation of innovators and problem solvers. As a sponsorsupporter of the nonprofit humanitarian organizationorganizations Engineers Without Borders USA and Engineers Without Borders Canada, we are committed to helping communities in developing countries meet their basic human needs through lasting, scalable projects and technologies.



Tetra Tech 2024 Proxy Statement 11

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Table

Human Capital Management
Human Capital Management
Tetra Tech brings together engineers and technical specialists from all backgrounds to solve our clients’ most challenging problems. At the end of Contents

FY 2023, we had 27,000 employees worldwide. A large percentage of our employees have technical and professional backgrounds and undergraduate and/or advanced degrees. Our professional staff includes, but is not limited to, analysts, archaeologists, architects, biologists, chemical engineers, chemists, civil engineers, data scientists, computer scientists, digital engineers, economists, electrical engineers, environmental engineers, environmental scientists, geologists, hydrogeologists, mechanical engineers, software engineers, statisticians, oceanographers, project managers, and toxicologists.
Health and Safety
We are committed to providing and maintaining a healthy and safe work environment for our employees. We provide training to employees to support the safe execution of their work and improve their understanding of behaviors that can be perceived as discriminatory, exclusionary, and/or harassing and provide safe avenues for employees to report such behaviors. We implement best practices and comply with local regulatory requirements. Our people understand acceptable workplace behavior as covered in our Corporate Code of Conduct. Further, as health and safety has always been a fundamental value at Tetra Tech, we report on two standard metrics: Lost Workday Incident Rate (LWDIR) and Total Recordable Incident Rate (TRIR). We have added two metrics that measure employee engagement in our H&S outreach programs and trainings and developed goals for these metrics, as reported in our 2023 Sustainability Report.
Health and Safety Results and Goals
MeasureRelated GRI
Performance
Indicator
2022 ResultsChange from 20212030 Goal
Lost Workday Incident
Rate (LWDIR) and
Total Recordable Incident Rate (TRIR)
GRI 403-2
LWDIR 80% better than industry average5
TRIR 75% better than industry average5
7% improvement
9% improvement
[MISSING IMAGE: ic_leaf-bw.jpg]
[MISSING IMAGE: ic_leaf-bw.jpg]
Continual improvement toward achieving and maintaining a zero LWDIR and a TRIR better than the industry average5
Employee Participation: Safety Month OutreachGRI 102-431,113,181 engagements16% increase[MISSING IMAGE: ic_leaf-bw.jpg][MISSING IMAGE: ic_roundtick-bw.jpg]
10% increase from
baseline
Employee Participation: Training CompletedGRI 404-145,573 H&S-related training modules completed by employees18% increase[MISSING IMAGE: ic_leaf-bw.jpg][MISSING IMAGE: ic_roundtick-bw.jpg]
10% increase from
baseline
OUR BOARD OF DIRECTORS
4 Health & Safety metrics are based on operational entities as defined for incident tracking

5 NAICS Code 54 Professional, Scientific, and Technical Services, BLS Data 2021
We believe supporting a safe and inclusive workplace is everyone’s responsibility in every office and on every project. In 2022, the most recent year for which full year data is available, our enterprise-wide TRIR was 0.23, 75 percent better than the industry average, and LWDIR was 0.06, 80 percent better than the industry average. In 2023 employees completed approximately 70,000 health and safety-related training modules in multiple languages. Our Safety Month campaign saw over 1.3 million engagements across all internal and external platforms. In addition, Tetra Tech received the 2023 Diversity, Equity, and Inclusion Safety Champion award from the National Safety Council (NSC), the global center for safety expertise that has been working to create a culture of safety and eliminate the leading causes of preventable death and injury for 110 years. NSC recognized Tetra Tech for effectively embedding inclusion and diversity throughout our safety program, and promoting diversity and equity across our safety operations and workforce.

Tetra Tech 2024 Proxy Statement 12

TABLE OF CONTENTS OVERVIEW

Human Capital Management
Diversity, Equity & Inclusion
With a highly collaborative workforce of thousands of high performing individuals working from hundreds of offices around the world, Tetra Tech truly is a multinational, multicultural organization. We value the diversity, perspectives and experiences that our employees bring to their engagement with co-workers and to their appreciation of our clients’ needs and objectives. With a highly collaborative workforce of thousands of employees working from hundreds of offices around the world, Tetra Tech truly is a multinational, multicultural organization.
Tetra Tech has received recognition for its Diversity, Equity, & Inclusion (DEI) program and company culture that promote a working environment and community where employees are valued for their contributions including winning the Environmental Business Journal’s inaugural Diversity & Inclusion Award and the NSC’s 2023 Diversity, Equity and Inclusion Safety Champion Award discussed above.
Our DEI Policy guides the Board of Directors, management, employees, subcontractors, and partners in providing an inclusive culture. Our DEI Council monitors Tetra Tech’s diversity, equity, and inclusion practices and makes recommendations to the Board and CEO for any changes or improvements to our program. The Council includes representatives from across the Company who reflect the diversity and values of our employees.
Tetra Tech values diversity, equity, and inclusion and undertakes various efforts throughout our operations to promote these initiatives. We have set goals for diversity and gender that are reported in our 2023 Sustainability Report.
We promote DEI through key programs including:

Equal employment opportunity—Tetra Tech ensures that our practices and processes attract a diverse range of candidates and that candidates are recruited, hired, assigned, developed, and promoted based on merit and their alignment with our values.

Enhancing learning and development opportunities—To support our employees in reaching their full potential, Tetra Tech offers a wide range of internal and external learning and development opportunities. Education assistance is offered to financially support employees who seek to expand their knowledge and skill base.
DEI-relevant training is required for all Tetra Tech employees as part of our company-wide ethics and compliance program. Required DEI-relevant training educates all employees on how to manage bias through the employment relationship, as well as avoiding offensive behavior and workplace harassment. Above and beyond this required training, Tetra Tech has built a DEI training resource library that includes online courses that enable all employees to gain insights into DEI perspectives and learn individual behaviors that can foster a more inclusive environment. Tetra Tech’s DEI training library is accessible to all employees.
Tetra Tech also provides DEI trainings and webinars throughout the year to foster and reinforce a culture of inclusivity. We educate hiring managers and employees on myriad forms of unconscious bias. By example, we provide guidance on how to recognize and avoid gendered language in our internal and external communications, as well as how to maximize digital accessibility so that content can be used by disabled people as easily as by non-disabled people.

Employee Resource Groups—As part of Tetra Tech’s commitment to a culture of inclusion, our Employee Resource Groups (ERGs) broaden and enhance companywide interaction opportunities for our employees. Tetra Tech’s global ERG program supports our employees and creates collaborative teams, or ERGs, where all voices are heard, all employees feel safe, and each employee has the opportunity to thrive. Our ERGs are open to all and involve activities for both employees whose background is the focus of the ERG and those who are supportive of the group (also known as allies). These global networks build on and coordinate with the many local networks already active throughout our operations and include groups focused on the experiences of Black, Latino/Hispanic, Pan-Asian, Women, Veterans, Disabled, and LGBTQIA+ employees and emerging professionals. Through our ERGs, we have established partnerships with the National Society of Black Engineers, Society of Hispanic Professional Engineers, Neurodiversity in Business, and Wounded Warrior Project. Our DEI Council charters and guides the development of the global ERGs to support our thriving worldwide employee community.

Tetra Tech Partners—Tetra Tech’s DEI practices have also been effective at broadening engagement with minority- and women-owned enterprises (MBE/WBEs), including indigenous peoples. Tetra Tech’s Small Business Council functions to identify diverse and disadvantaged businesses with qualifications that can add value to our global projects. In 2022, the US Small Business Administration awarded Tetra Tech the prestigious Dwight D. Eisenhower Award for Excellence in the Services Category for our effective small business subcontractor program. Tetra Tech is a five-time winner of the U.S. Small Business Administration’s prestigious Dwight D. Eisenhower Award for Excellence for our effective small business subcontractor program. Our robust supply chain enables us to engage with small, local, and diverse enterprises across all socioeconomic categories,

Tetra Tech 2024 Proxy Statement 13

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Human Capital Management
including MBEs, WBEs, small-disadvantaged businesses, and Historically Black Colleges and Universities/Minority Institutions (HBCU/MI). Tetra Tech is also active in the U.S. Small Business Association’s mentor-protegee program, where we work to develop and mentor minority or disadvantaged business. Tetra Tech has several protégé’s including an Alaskan Native Corporation 8a Business, a Woman-Owned Small Business, and a Service-Disabled Veteran-Owned Small business.
For additional information, visit our website at tetratech.com/diversity.
Professional Development
Tetra Tech invests in the professional development of our employees. This investment enables us to attract and retain the caliber of talent that is integral to our success as a high-end professional consulting and engineering company that is Leading with Science®, and we have one of the lowest employee turnover rates in our industry at just seven percent in 2023.
Professional development is essential to the successful performance of high-end projects and collaborative multidiscipline team delivery of responsive solutions. Working on challenging, innovative, and technically cutting-edge projects enhance our employees’ professional development and growth. Our work encompasses many sustainable, societal, and beneficial outcomes that enable our employees to make positive contributions that benefit society. Technically innovative projects also provide an opportunity for our employees to “advance the science” in leading applications of our expertise to water, environment, sustainable infrastructure, and international development projects worldwide. We encourage our employees to develop patents, where appropriate, and to publish journal articles in their field of expertise, often in collaboration with our clients. With our 550 offices worldwide, our employees can meaningfully contribute to improving the quality of life for the communities in which they work and live.
The Tetra Tech Academy provides access to all employees to training, technical exchange and collaboration, and skill development resources through its customized Learning Management System, providing professional development opportunities throughout our employees’ careers. Technology skills development includes access to a series of live webcasts and recorded technology transfer sessions. Company-wide networking events provide interactive skills development activities. Employees are also provided with access to training in leadership development, project management skills, and interpersonal skills development. Various personal development and wellness programs are sponsored by our Human Resources team. Our Corporate Information Technology team provides access to software training and skills development modules to all employees. Tetra Tech also supports our employees in discipline specific training, certifications, and accreditation programs across the Company. Programs such as specific health and safety programs, hazardous waste investigation, environmental certifications, and professional certifications are encouraged as per client, project and professional development needs.
In addition, we have specific focused programs which are designed, taught, and facilitated by Tetra Tech leadership, technical experts, experienced program managers, as well as accredited external resources. These programs include:

Project Management Training Program—Tetra Tech develops project managers who are world class in their abilities and performance. Tetra Tech’s Project Excellence Steering Committee (PESC) sponsors the development and implementation of our comprehensive Project Management Training Program. The training program has been designed to address all areas of the project life cycle. Tetra Tech’s Project Management Training Program is available to all employees and is focused on professional development, techniques for managing high-end projects and how to employ enterprise systems, dashboards and proprietary technology tools. Our Project Management Training Program provides comprehensive training in high-end project leadership skills through on-line training, virtual workshops, and in-person events, where attendees progress through three development tiers.

Fearless Entrepreneur Program—Tetra Tech develops employees into client oriented, business minded professionals who are driven to understand and meet the needs of our clients. Through this company-wide program, developing professionals are challenged and mentored through a process of building client relationships. Participants take part in group discussions in a classroom setting and then are required to implement learned strategies with actual and potential clients. This program is led by senior operations management and completion is certified by an executive officer of the Company.

Employee Resource Group (ERG) Sponsored Training—ERGs provide training, networking, and mentoring opportunities accessible to all Tetra Tech employees. For example Tetra Tech’s Professional Women’s Network provides a monthly platform for issues that affect women in the workplace. Tetra Tech women at various levels of leadership share insights and knowledge acquired throughout their careers. This group provides the opportunity for women at any stage in their careers to ask questions and further their career development by connecting them with mentors across the Company.

Tetra Tech 2024 Proxy Statement 14

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Human Capital Management

Tetra Tech Technology Transfer (T4) and ToolTalk Webcast Series—Tetra Tech holds technology focused webcasts accessible to all employees around the world, to provide information and resources to improve their use of available internal tools and develop their technical skills. Through the T4 and ToolTalk Webcast Series, Tetra Tech experts and academics present and lead discussions about new technologies and programs, best practices, and opportunities for growth across the Company. All employees are invited to participate in the live presentations or view webcast recordings, ensuring that we are growing the knowledge, strength, and leadership of our employees around the world.

Tech 1000 Challenge—The Tech 1000 Challenge is a competition among one thousand of the company’s staff to create the most innovative, technology focused solution to a real client challenge. The event brings together employees from around the world to team up and vie for the top technology solutions that address our clients’ needs. Participants from across our markets form teams to focus on client needs, receive briefings on our Tetra Tech Delta technologies from their peers, and hone their skills in designing strategies and pitching client solutions. Participants are provided in-depth training on technology, marketing, branding, tools development, and software business practices. Top ranked teams also receive mentoring and support to further develop their ideas. Access to technology briefings and tools is provided to all employees as a result of the challenge event.

Discipline Specific Training and Accreditation—Tetra Tech supports our employees in discipline specific training, certifications, and accreditation programs across the Company. Programs such as specific health and safety programs, hazardous waste investigation, environmental certifications, and professional certifications are encouraged as per client, project and professional development needs.

Leadership Academy—Tetra Tech’s Leadership Academy develops our high potential employees from around the world into outstanding business leaders. Instructors for this intensive, year-long program are executive management and operational leaders from within the Company. Participants are immersed in all aspects of the operations of the Company and complete challenging, real-world assignments designed to hone their leadership and management skills. Completion is personally certified by the Company’s CEO and Chairman of the Board.

Executive Development Initiative—Tetra Tech further develops our senior-level leaders into effective, well-rounded executives. Participants complete a variety of assessments, including 360 reviews, and engage in extensive career development mentoring, which result in development goals and opportunities for greater engagement throughout the Company and leadership of our employees around the world.
By offering our employees meaningful work and continuous career development opportunities, Tetra Tech is well positioned to continue our growth through recruitment, development, and retention of the best talent in the industry.

Tetra Tech 2024 Proxy Statement 15

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Our Board of Directors
Our Board of Directors
Our Board of Directors is responsible for overseeing, counseling, and directing management in serving the long-term interests of our companyCompany and stockholders, with the goal of building long-term stockholder value and ensuring the strength of our companyCompany for our clients, employees, and other stakeholders. In this capacity, the Board'sBoard’s primary responsibilities include establishing an effective corporate governance program,Corporate Governance Program with a Boardboard and Committeecommittee structure that ensures independent oversight; overseeing our business, strategies (including mergers and acquisitions), and risks; maintaining the integrity of our financial statements; evaluating the performance of our senior executives and determining their compensation; undertaking succession planning for our CEO, and other senior executives;executives, and directors; and reviewing our annual operating planAnnual Operating Plan (AOP) and significant strategic and operational objectives and actions.

BOARD COMPOSITION

Board Composition
Our bylaws provide that our Board shall consist of between five and ten10 directors, with the exact number fixed from time to time by Board resolution. The Board has fixed the number at nine. We believe a limited number of directors helps maintain personal and group accountability. The Board, which currently consists of eight members, has reduced the number to seven directors as of the end of the 2024 Annual Meeting. Our Board is majority independent in composition and outlook, other than our CEO.outlook. All of our current directors, with the exception of Mr. Thompson who will retire at the 2024 Annual Meeting, have been nominated for election by the Board of Directors upon recommendation by the NCG CommitteeCommittee.
Board Meetings and have decided to stand for election.

Attendance

Name


Director
Since


Principal Occupation
Independent
AC
CC
GC
SC

Dan L. Batrack

2005Chairman and CEO, Tetra Tech, Inc.No

Hugh M. Grant

2003Retired Vice Chair & Regional Managing Partner, Ernst & Young LLPYesCM

Patrick C. Haden

1992President, Wilson Avenue ConsultingYesMM

J. Christopher Lewis

1988Managing Director, Riordan, Lewis & HadenYesMM

Joanne M. Maguire

2016Retired Executive Vice President, Lockheed Martin Space Systems CompanyYesCM

Kimberly E. Ritrievi

2013President, The Ritrievi Group LLCYesMM

Albert E. Smith (PD)

2005Retired Executive Vice President, Lockheed Martin CorporationYesMC

J. Kenneth Thompson

2007President and CEO, Pacific Star Energy, LLCYesCM

Kirsten M. Volpi

2013Executive Vice President, Chief Operating Officer, and Chief Financial Officer and Treasurer, Colorado School of MinesYesMM

AC = Audit Committee         CC = Compensation Committee         GC = Nominating and Corporate Governance Committee
SC = Strategic Planning and Enterprise Risk Committee         M = Member         C = Chair         PD = Presiding Director


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BOARD MEETINGS AND ATTENDANCE

During fiscal 2017,FY 2023, our Board of Directors held eightsix meetings. During thisthat period, all of the incumbent directors attended or participated in 100% of the aggregateat least 75% of the total number of meetings of the Board and the total number of meetings held by allthe committees of the Board on which each such directorof those directors served during the period for which each such directorof them served. Our directors are strongly encouraged to attend the annual meeting of stockholders,2024 Annual Meeting, and all of our directors then in office attended last year's annual meeting.

CORPORATE GOVERNANCE POLICIES

              Our the 2023 Annual Meeting.

Corporate Governance Policies as updated in July 2017, provide the
Our corporate governance framework for our company and reflectpolicies, listed in the beliefs of our Board with respect to the matters described below. Theyfollowing table, are reviewed at least annually and amended from time to time to reflect the beliefs of our Board, changes in regulatory requirements, evolving marketbest practices, and recommendations from our stockholders and advisors.

Corporate Governance Policies
MatterDescription of Policy
Board Composition



Matter





Description of Policy



​ ​ ​ ​ 
​  Board Composition


Reasonable Size. Our Board isshall be between five and ten10 directors.


No Over-BoardedOverboarded Directors. Our directors sit on three or fewer boards of other public company boards.

companies.


Mandatory Retirement. Our Board has fixed the retirement age for directors at 75; however, Mr. Grant has been exempted because of his special qualifications and experience, and the75.

Tenure Limit. Our Board has waived this mandatory retirement requirement solelyset the maximum tenure for him. There are no established term limits on service.

non-employee directors at 12 years, except that the maximum tenure is 15 years for directors whose service began prior to 2014.
​ ​ 
Director Independence

Majority Independent. A majority of our directors satisfy the Nasdaq independence standards.


Regular Executive Sessions. Our independent directors meet in executive session following each regular meeting of the Board, each meeting of the Audit Committee, and certain other Committeecommittee meetings.

​ ​ 
Board Leadership Structure

Robust Presiding Director Role. Since our CEO is also Chairman, our independent directors selectedselect one of themselves to serve on a rotating basis as Presiding Director, with established roles and responsibilities. See "the Board Leadership Structure"Structure section following this table on page 17 for further details.


Annual Review. The Board annually appoints a Chair and determines whether the positions of Chair and CEO will be held by one individual or separated.


Tetra Tech 2024 Proxy Statement 16

Our Board of Directors
​ ​ MatterDescription of Policy
Board Committees

Independence. Board Committeescommittees are comprised only of independent directors.


Governance. Board Committeescommittees act under written charters settingthat are evaluated by the Board annually that set forth their purposes and responsibilities, which charters are evaluated annually.responsibilities. The charters allow for the engagement, at our expense, of independent legal, financial, or other advisors as the directors deem necessary or appropriate.


Attendance. Directors prepare for and are expected to attend all meetings of ourthe Board and its Committeescommittees on which they serve and are strongly encouraged to attend all annual stockholder meetings.

Annual Meetings.
Director Qualifications

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Matter





Description of Policy



​ ​ ​ ​ 
​  Director QualificationsDiverse and Relevant Experience. The NCG Committee works with the Board to determine the appropriate characteristics, skills, and experiences for the directors. We are committed to selecting candidates regardless of gender, ethnicity and national origin.
​ ​ 
Board DutiesManagement

Succession Planning.Planning. Our Board conducts executive and director succession planning annually, including progress in current job position and career development in terms of strategy, leadership, and execution.


Financial Reporting, Legal Compliance, and Ethical Conduct. Our Board maintains governance and oversight functions, but our executive management maintains primary responsibility.


Stock Ownership Guidelines. To align the interests of stockholders with the directors and executive officers, our Board has established stock ownership guidelines.

guidelines applicable to executive officers and directors.
​ ​ 
Continuous Board Improvement

New Director Orientation. All new directors participate in an orientation program to familiarize themselvesthem with our company.

Company.


Continuing Education. Directors continue their education through meetings with executive management and other managers to enhance the flow of meaningful financial and business information. They also receiveare given presentations to assist with their continuing education.

Directors also attend outside director education programs to stay informed about relevant issues.


Annual Performance Evaluations.Evaluations. The NCG Committee oversees an annual self-assessment process for the Board and its committees to ensure our Board and each of the Committeescommittees are functioning effectively.

Director Independence

DIRECTOR INDEPENDENCE

Upon recommendation of the NCG Committee, our Board of Directors has determined that each member ofMr. Birkenbeuel, Mr. Gandhi, Ms. Maguire, Ms. Obiaya, Dr. Ritrievi, Mr. Thompson (who will retire at the Board of Directors other than Mr. Batrack is2024 Annual Meeting), and Ms. Volpi are each independent under the criteria established by Nasdaq for director independence. Mr. Batrack is not independent because he is an employee.

              In connection with the assessment of Mr. Thompson's independence, we reviewed the facts and circumstances of his roleserving as an independent director of Coeur Mining, Inc. and Pioneer Natural Resources Company, two of our clients, and Alaska Air Group, Inc., one of our vendors. We concluded that Mr. Thompson is an independent director because his role at each of these companies is limited to that of an independent director, each of the companies is a large public company, and the amount of business done with each of the companies is immaterial to us (less than 1% of our fiscal 2017 net revenue) and each such company.

CEO.

All members of each of our Audit, Compensation, NCG, and Strategic Planning and Enterprise RiskSPER committees are independent directors. In addition, the members of the Audit Committee meetand Compensation Committee each meets the additional independence criteria required for audit committee membership on those committees under applicable Nasdaq listing standards, andstandards. The Board also has determined that each has been determined by our Board to bemember of the Audit Committee qualifies as an "audit“audit committee financial expert"expert” under SEC rules.


Board Leadership Structure

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              There were no payments by third parties to any of our directors or director nominees in connection with their candidacy for, and/or service on, our

Our Board of Directors.

GRAPHICGRAPHIC

BOARD LEADERSHIP STRUCTURE

Directors does not have a policy with respect to whether the roles of Chairman and CEO should be separate or combined. We currently have a combined Chairman/CEO role as well as an independent Presiding Director. We believe that the combined Chairman/CEO role is appropriate because it allows for one individual to lead our companyCompany with a cohesive vision, the ability to execute that vision, and the understanding of the significant enterprise risks that need to be mitigated or overcome to achieve that vision. It also fosters clear accountability, effective decision-makingdecision making, and alignment on corporate strategy. Combined leadership at the top also provides the necessary flexibility for us to rapidly address the changing needs of our business.

Balancing our combined Chairman/CEO is our Presiding Director, elected bywho is independent and from the independent directors, who has critical duties in the boardroom to ensure effective and independent oversight of Board decision-making. In November 2015, thedecision making. The Board has determined that the role of Presiding Director wouldwill rotate to ensure independence and the term wouldwill be four years. At a meeting in January 2016,February 2023, the independent directors elected Mr. SmithMs. Maguire to serve as Presiding Director for a four-year term ending in late January 2020.

2027.


Tetra Tech 2024 Proxy Statement 17

Our Governance PoliciesBoard of Directors
Our governance policies describe the Presiding Director'sDirector’s duties, which delineate clear responsibilities to ensure independent stewardship of our Board, as summarized below.

Presiding Director Roles and Responsibilities:Responsibilities

scheduling

Schedule meetings of the independent directors;

directors

chairing the

Chair separate, executive session meetings of the independent directors;

directors

serving

Serve as principal liaison between the independent directors and the Chairman/CEO on sensitive issues;

communicating

Communicate with the Chairman/CEO and disseminatingdisseminate information to the rest of the Board of Directorsremaining directors as appropriate;

appropriate

providing

Provide leadership to the Board of Directors if circumstances arise in which the role of the Chairman may be, or may be perceived to be, in conflict; and

conflict with the Company

being

Be available, as appropriate, for consultation and direct communication with stockholders.

major stockholders

Oversee, with the NCG Committee, the annual self-evaluation of the Board

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Supplementing the Presiding Director are our Committee Chairscommittee chairs and members, all of whom are independent. With the Compensation Committee conducting a rigorous annual evaluation of the CEO'sCEO’s performance, thatwhich is discussed by all independent directors during executive sessions, we believe our Board leadership structure provides independent oversight of our company.

BOARD COMMITTEES

Company.

Board Committees
Each of our Board committees has a separate written charter that describes its purposes,purpose, membership, meeting structure, authority, and responsibilities. These charters, which maycan be found in the CorporateESG Governance Overview section of our website atwww.tetratech.com/en/corporate-governance, investor.tetratech.com/esg/governance-overview, are reviewed annually by the respective committee, on an annual basis, with any recommended changes adopted upon approval by ourthe Board. Updated charters are promptly posted on our website.

              We have

The Board has four standing committees consisting solely of independent directors, each with a different independent director serving as chairpersonchair of the committee. Our Boardstanding committees are:are the Audit Committee, the Compensation Committee, the NCG Committee, and the Strategic Planning and Enterprise RiskSPER Committee. We hold our Board committee meetings are held sequentially (i.e., committee meetings do not overlap with one another). As a result of holding sequential meetings, and enable each of our Board members is given the opportunity to attend each committee meeting. We believe this practice is highly beneficial to our Board as a wholespecifically and to the companyCompany in general because each of our Board members is aware of the detailed work conducted by each Board committee. This practice also affords each of our Board members the opportunity to provide input to theeach committee members before any conclusions are reached.



Tetra Tech 2024 Proxy Statement 18

The primary responsibilities, membership, and meeting information for our four standing committees are summarized below.

Standing Committees of the Board of Directors
Audit Committee
Meetings in FY 2023: 4

Audit Committee



​ ​ ​ ​ Average Attendance in FY 2023: 100%

Current Members:

    Hugh M. Grant (Chair)
    J. Christopher Lewis

Chair
Gary R. Birkenbeuel
Members
Kimberly E. Ritrievi

Kirsten M. Volpi

Meetings in Fiscal 2017:    6

Average Attendance in Fiscal 2017:
    100%

All members satisfy the audit committee experience and independence standards required by Nasdaq and have been determined to be financially literate.

Each member of the Audit Committee has been determined to be an "audit“audit committee financial expert"expert” under applicable SEC regulations.

Responsibilities:

Responsibilities

reviewing

Review our significant accounting principles, policies, and practices in accounting for and reporting our financial results under generally accepted U.S. accounting principles;

principles

reviewing

Review our annual audited financial statements and related disclosures;

disclosures

reviewing

Review management letters or internal control reports and reviewingreview our internal controls over financial reporting;

reporting

reviewing

Review the effectiveness of the independent audit effort;

effort

appointing, retaining

Appoint, retain, and overseeingoversee the work of the independent accountants;

accountants

pre-approving

Pre-approve audit and permissible non-auditnon audit services provided by the independent registered public accounting firm;

firm

reviewing

Review our interim financial results for each of the first three fiscal quarters;

quarters

reviewing

Review management’s analysis of significant accounting issues, changes, estimates, judgments or unusual items relating to financial statements and discussing the reports ofcritical accounting policies

Be directly responsible for our internal Management Audit Department;

reviewingDepartment, approve its audit plan, and discussingreview its reports


Review and discuss financial, liquidity, tax and treasury, litigation, and Sarbanes-Oxley (SOX)Sarbanes Oxley Act of 2002 compliance matters in accordance with our enterprise risk management (ERM) responsibility matrix;

matrix

reviewing

Review and overseeingoversee related party transactions;

transactions

reviewing

With the Compensation Committee, approve the compensation of our CFO

Review and establish procedures for receipt, retention, and treatment of complaints regarding accounting, internal controls, or auditing, matters;employee, and

other matters

preparing

Prepare the annual Audit Committee Report to be included in the proxy statement.

statement

Meet at least quarterly with the independent accountants, and if necessary, the CFO or a member of the Management Audit Department
Nominating and Corporate Governance Committee
Meetings in FY 2023: 3Average Attendance in FY 2023: 100%

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Compensation Committee



​ ​ ​ ​ 

Current Members:

Chair
Joanne M. Maguire
Members
Gary R. Birkenbeuel
Prashant Gandhi
J. Kenneth Thompson (Chair)
    Patrick C. Haden
    J. Christopher Lewis
    Kirsten M. Volpi

Meetings in Fiscal 2017:    5

Average Attendance in Fiscal 2017:
    100%

All members satisfy the independence standards required by Nasdaq.

Responsibilities

Develop criteria for nominating and appointing directors, including board size and composition; corporate governance policies; and individual director expertise, attributes, and skills

Recommend to the Board the individuals to be nominated as directors

Recommend to the Board the directors to be selected for service on the Board committees

Develop, annually assess, and make recommendations to the Board concerning appropriate corporate governance policies

Oversee an annual review of the performance of the Board and each committee and report the results thereof to the Board

Review annually the adequacy of the committee charters and recommend to the Board proposed changes

Make recommendations to the Board on changes in the compensation of nonemployee directors

Review the succession plans relating to the positions held by executive officers and directors

Review our Corporate Code of Conduct and anti-fraud policies in accordance with our ERM responsibility matrix; and consider any conflict-of-interest issues between the Company, its directors or executive officers

Consider any conflict of interest issues between the Board or executive officers and the Company

Tetra Tech 2024 Proxy Statement 19

Our Board of Directors
Strategic Planning and Enterprise Risk Committee
Meetings in FY 2023: 3Average Attendance in FY 2023: 100%
Chair
Kimberly E. Ritrievi
Members
Prashant Gandhi
Christiana Obiaya
All members satisfy the independence standards required by Nasdaq.
Responsibilities

Oversee our strategic planning process

Provide oversight of the development of our three-year strategic plan by the management team

Review and recommend to the Board certain strategic decisions regarding our exit from existing lines of business, entry into new lines of business, acquisitions, joint ventures, investments in or dispositions of businesses, and review and approval of our capital allocation strategy

Review, as requested by management, our bid and proposal strategy for high risk contracts

Oversee our ERM policies and procedures and work with our Corporate Risk Management Officer on ERM reports to the Board

Oversee our ESG policies, procedures, and reporting, including climate matters and climate-related risks

Review and discuss with the Company’s Chief Information Officer material risks relating to data privacy, technology and information security, including cybersecurity, threats and back-up of information systems and the Company’s processes for assessing, identifying, and managing such risks, as well as the Company’s internal controls and disclosure controls and procedures relating to cybersecurity incidents
Compensation Committee
Meetings in FY 2023: 4Average Attendance in FY 2023: 100%
Chair
J. Kenneth Thompson
Members
Joanne M. Maguire
Christiana Obiaya
Kirsten M. Volpi
All members satisfy the independence standards required by Nasdaq.
All members qualify as "non-employee directors"“nonemployee directors” under Rule 16b-3 of the Securities Exchange Act of 1934, as amended,Act.
Responsibilities

Review and as "outside directors" under Section 162(m) of the Internal Revenue Code.

Responsibilities:

reviewing and approvingapprove the annual base salaries and annual incentive opportunities of the CEO and other executive officers, including an evaluation of the performance of the executive officers in light of our performance goals and objectives;

objectives

reviewing

Review and approving, as they affect the executive officers,approve all other incentive awards and opportunities, any employment agreements and severance arrangements, any change-in-controlchange in control agreements, and any special or supplemental compensation and benefits;

benefits as they affect the executive officers

reviewing

Review and discussingdiscuss comments provided by stockholders and proxy advisory firms regarding our executive compensation;

compensation

overseeing

Monitor compliance with requirements under the Sarbanes Oxley Act of 2002 relating to loans to director and executive officers, and with all other applicable laws affecting employee compensation and benefits

Oversee our compliance with SEC rules and regulations regarding stockholder approval of certain executive compensation matters;

matters

reviewing

Review director and executive officer stock ownership under our Stock Ownership Guidelines;

stock ownership guidelines

reviewing

Review and discussingdiscuss incentives and rewards in accordance with our ERM responsibility matrix;

matrix

making

Make recommendations to the Board with respect to incentive-based compensation plans, equity-based plans, and executive benefits;

benefits

reviewing

Review and approvingapprove all grants of equity awards;

awards

reviewing

Review and discussingdiscuss the annual Compensation Discussion and Analysis and Compensation Committee Report to be included in the proxy statement;statement

Select, retain and

retaining and working work with the independent compensation consultant.

consultant
Executive Sessions

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Nominating and Corporate Governance Committee



​ ​ ​ ​ 

Current Members:

    Joanne M. Maguire (Chair)
    Hugh M. Grant
    Patrick C. Haden
    Albert E. Smith

Meetings in Fiscal 2017:    4

Average Attendance in Fiscal 2017:
    100%

All members satisfy the independence standards required by Nasdaq.

Responsibilities:

developing criteria for nominating and appointing directors, including Board size and composition, corporate governance policies, and individual director expertise, attributes and skills;

recommending to the Board the individuals to be nominated as directors;

recommending to the Board the appointees to be selected for service on the Board committees;

overseeing an annual review of the performance of the Board and each committee;

reviewing annually the adequacy of the committee charters and recommending proposed changes to the Board;

making recommendations to the Board on changes in the compensation of non-employee directors;

reviewing the succession plans relating to the positions held by executive officers;

reviewing our Code of Conduct and anti-fraud policies in accordance with our ERM responsibility matrix; and

considering any conflict of interest issues between us and directors or executive officers.


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Strategic Planning and Enterprise Risk Committee



​ ​ ​ ​ 

Current Members:

    Albert E. Smith (Chair)
    Joanne M. Maguire
    Kimberly E. Ritrievi
    J. Kenneth Thompson

Meetings in Fiscal 2017:    2

Average Attendance in Fiscal 2017:
    100%

All members satisfy the independence standards required by Nasdaq.

Responsibilities:

overseeing our strategic planning process, and working with management to plan the annual offsite Strategic Planning and Enterprise Risk meeting;

reviewing and recommending to the Board certain strategic decisions regarding our exit from existing lines of business, entry into new lines of business, acquisitions, joint ventures, investments in or dispositions of businesses, and reviewing and approving our capital allocation strategy;

reviewing, as requested by management, our bid and proposal strategy for high risk contracts;

overseeing our ERM policies and procedures, and working with our Corporate Risk Management Officer on ERM reports to the Board; and

reviewing, as determined by management, any changes in technology and regulatory trends to assess the impact of technology and regulatory changes on business strategy and resource allocation.

EXECUTIVE SESSIONS

Our Board believes it is important to have executive sessions without our CEO being present, which are scheduled after every regular meeting of the Board. Our independent directors have robust and candid discussions at these executive sessions during which they can critically evaluate the performance of our company,Company, CEO, and management.


Tetra Tech 2024 Proxy Statement 20

Our Board of Directors
In addition, executive sessions of the Audit Committee are scheduled following each regular meeting of the Audit Committee (with our independent auditors, with the head of our Management Audit Department,internal audit department, and with executive management, if deemed necessary), and. Also, an executive session of the Compensation Committee is scheduled following the Compensation Committee meeting each November, at which executive compensation determinations are made.

RISK OVERSIGHT

Oversight of Risk Management
Enterprise Risk Management (ERM) and Strategic Risks

We believe that risk is inherent in the pursuit of long-term growth opportunities. Our management is responsible for day-to-day risk management activities. The Board of Directors, acting directly and through its committees, is responsible for the oversight of our risk management. With this oversight, we have implemented an ERMEnterprise Risk Management (ERM) program with practices and policies designed to help manage the risks to which we are exposed in our business and to align risk-takingrisk taking appropriately with our efforts to increase stockholder value.


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The Strategic Planning and Enterprise RiskSPER Committee is responsible for the oversight of the ERM.ERM program. Our Corporate Risk Management Officer reports the status of the ERM program to this committeethe SPER Committee on a semi-annual basis.semiannual basis, in addition to quarterly reports to the Audit Committee. The reports address our risk management effectiveness, those projects that maymight significantly impact our financial condition, and any new risk issues and mitigation measures that have been implemented.

              As part The SPER Committee, as well as other members of the Board, also receive regular updates from our Chief Information Officer on the overall cybersecurity risk oversight framework, otherenvironment, including our Company’s enterprise-wide cybersecurity governance, risk assessment results and key initiatives.

Other committees of the Board also oversee certain categories of risk associated with their respective areas of responsibility to better coordinate with management and serve the long-term interests of our stockholders. OurThe reports the Board receives reports from the committees regardingcovering topics discussed at the committeetheir meetings which include any discussion of the areas of risk overseen primarily by the committees.

each committee.

In addition, the Board participates in regular discussions among the directors and with our senior management with respect toon several core subjects in which risk oversight is an inherent element, including strategy, operations, finance, mergers and acquisitions (M&A), and legal matters. The Board believes that the leadership structure described above under "Boardin the Board Leadership Structure"Structure section on page 17 of this proxy statement facilitates the Board'sBoard’s oversight of risk management because it allows the Board, with leadership from the Presiding Director and working through its committees, to participate actively in the oversight of management'smanagement’s actions.


OVERSIGHT OF RISK

Major Areas of Oversight of the Board and Standing Committees



Board or Committee





Major Areas of Responsibility



​ ​ ​ ​ 
​  Board of Directors

Annual operating plan;

Corporate governance;

Major initiatives;

Mergers and acquisitions;

Business development;

Project execution; and

Major markets and clients

​ ​ 
​  Audit Committee

Financial metrics and measures;

Liquidity and cash flow;

Tax and treasury strategy;

Fiscal discipline;

Litigation and claims; and

Sarbanes-Oxley compliance

​ ​ 
​  Compensation Committee

Management incentives and awards

​ ​ 
​  Nominating and Corporate Governance Committee

Code of Conduct; and

Anti-fraud policies

​ ​ 
​  Strategic Planning and Enterprise Risk Committee

Business planning and performance;

Risk appetite and tolerance;

Bids and proposals;

Capital structure;

Technology risk; and

Corporate ERM

[MISSING IMAGE: fc_areas-pn.jpg]

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Risks Associated with Compensation Policies and Practices

As described in theCompensation Discussion and Analysis section on page 37 of this proxy statement, we maintain what we believe are best practices in compensation and corporate governance that collectively encourage ongoing risk assessment and mitigation. The Compensation Committee periodicallyregularly reviews our executive compensation program to ensure that it does not provide incentives that

Tetra Tech 2024 Proxy Statement 21

Our Board of Directors
encourage our employees to take excessive risks in managing their respective businessesbusiness or functional areas. Our compensation program includes the following safeguards:

the
The program balances executive retention with rewarding stockholder value creation;

creation
the
The majority of executive compensation is variable,at risk, with a mix that is consistent with market practices and primarily equity-basedequity based to promote long-term performance and sustainable growth;

the
The incentive mix is balanced, with short- and long-term performance metrics that do not overlap, cover different time periods, and are balanced among annual financial objectives and long-term economic and stockholder value creation;

creation
our AIP
Our annual incentive plan (AIP) and LTIs appropriately balance profitable growth in the near term with sustainable long-term financial success, use multiple performance metrics, measure performance at multiple levels (corporate, business group, and individual), and provide realized compensation based primarily on our performance;

performance
the
The Compensation Committee may exercise downward discretion to adjust the objective, formulaic AIP awards based on individual performance;

performance

AIP awards are not guaranteed with below threshold performance yielding zero payout, and paymentsare subject to an overall cap of 200% of an executive's target AIP award;

maximum payout caps
our
Our incentive metrics and performance goals have multiple approval levels and oversight levels, including approval by members of the Compensation Committee;

Committee
our PSU
Our performance stock unit (PSU) awards are performance-based,performance based, use multiple performance metrics, are subject to maximum payout opportunitiescaps to encourage appropriate performance focus and to limit potential risk-taking,risk taking, and cliff vest at the end of three years;

years
our
Our change of control plans are reasonable and appropriate,plan is market aligned, with change of control benefits provided on a double-triggerdouble trigger basis and these benefitsthat do not provide excessive incentive to seek a transaction and are not grossed up for excise taxes;

taxes
our
Our clawback policy and stock ownership guidelines are consistent with market practices; and

practices
our
Our stock ownership guidelines, annual stock awards, and vesting provisions create sustained and consistent ownership stakes.

stakes

Based on these and other factors as well as on the advice of its independent compensation consultant, the Compensation Committee has concluded that our compensation policies and practices strike an appropriate compensation-riskcompensation risk balance, do not encourage excessive risk-takingrisk taking, and do not as a whole create risks that are reasonably likely to have a material adverse effect on our company.

Company.

Succession Planning

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SUCCESSION PLANNING

Our Board is involved in the identification and cultivation of our future leaders. We maintain an annual performance review process and leadership development program for our key employees. Management develops leadership at lowerall levels of our organization by identifying core talent, cultivating the skills and capabilities that will allow identified individuals to become our future leaders, assessing their development, and identifying gaps and developmental needs in skills and experience. At its meetings, the Board has the opportunity to meet with leaders of our company,Company, including business group leaders and leaders in finance, law, information technology, risk management, strategy health and safety, and human resources. In addition, Board members have freedom of access to key employees.

The NCG Committee conductsis responsible for conducting executive succession planning annually, including progress in current job position and career development in terms of strategy, leadership, and execution. During this review, the CEO and the independent directors discuss future candidates for senior leadership positions, succession timing for those positions, and development plans for the highest-potential candidates.candidates with the highest potential. This process ensures continuity of leadership over the long term and it forms the basis on which we make ongoing leadership assignments.

BOARD AND COMMITTEE EVALUATIONS

In addition, the NCG Committee is responsible for conducting director succession planning and the selection of director nominees as discussed below.

Director, Board, and Committee Evaluations
The NCG Committee oversees and conducts an annual evaluation of our directors, Board, and Board committees. For the Board, the comprehensive self-assessment covers areas such as effectiveness, composition, culture, resources, and meetings. Each of the 35 topics within these areas is scored from 1 (Needs Improvement) to 5 (Role Model), with 3 being Acceptable. The Board then discusses each topic, with a particular focus on any topic that has received a score from any director of 3 or less.

less from any director.


Tetra Tech 2024 Proxy Statement 22

Our Board of Directors
The directors also comment on the Board'sBoard’s most significant contributioncontributions to the companyCompany during the last 12 months, the most important issues for the Board shouldto address in the next 12 months, and theany areas in which the companyCompany could improve its Boardthe Board’s management practices. TheseThose comments result in action items that are placed on the agenda and addressed in subsequent Board meetings.

For each of the Committees,committees, the self-assessment covers areas such as Committeecommittee composition, effectiveness, structure, information and resources, and meetings. As with the Board self-assessment, each of the topics within these areas is scored from 1 to 5. The members of the Committeecommittee also comment on the Committee'scommittee’s greatest contribution to the companyCompany during the last 12 months and the most important issues for the Committee shouldcommittee to address in the next 12 months. The Chairchair of each Committeecommittee then leads a discussion of each area among the Committeecommittee members, of each topicwith a particular focus on any area that has received a score from any Committee member of 3 or less and of the general comments.from any committee member. The responsescomments result in action items that are placed on the agenda and addressed in subsequent Committeecommittee meetings.

Many of the improvements in our corporate governance practices and Boardboard and Committeecommittee processes have resulted from thethis annual evaluation process. Our Board views the annual evaluation process as an integral part of its commitment to cultivating excellence and best practices in its performance.

ACTIVE STOCKHOLDER ENGAGEMENT AND COMMUNICATIONS POLICY

Governance Engagement

              We value our stockholders' opinions about our governance policies and practices, and we actively solicit input through our stockholder engagement program. In advance

Selection of the 2018 Annual


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Meeting, we proactively contacted our largest institutional stockholders, representing a majority of our then-outstanding shares, to solicit their views on our corporate governance and executive compensation programs. We welcome feedback on our corporate governance program that this active and ongoing engagement with stockholders provides.

Contacting the Board

              Stockholders may contact our Board, Chairman, Presiding Director any Committee or Committee Chair, or any other individual director concerning business-related matters by writing to: Board of Directors (or a particular subgroup or individual director), c/o Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107; or via email toasktheboard@tetratech.com.


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Nominees
ITEM 1 – ELECTION OF DIRECTORS

              Our bylaws provide for a Board of between five and ten directors, with the exact number fixed from time to time by a resolution of our Board. The Board has fixed the number at nine, and there are currently nine directors on our Board. All of the incumbent directors are nominated for election at the Annual Meeting for a one-year term. Each of the nine nominees has consented to being named in this proxy statement and to continue serving if elected.

MAJORITY VOTING STANDARD

              Our bylaws provide for the majority voting of directors in uncontested elections like this one. Consequently, in order to be elected, a nominee must receive more votes "for" than "against" and the number of votes "for" must be at least a majority of the required quorum. Should any of the nominees fail to receive the vote required to be elected in accordance with our bylaws, that director must promptly tender his or her resignation to the Board of Directors. In that event, the NCG Committee will make a recommendation to the Board as to whether to accept or reject the tendered resignation, or whether other action should be taken. The Board will then act on the tendered resignation, taking into account the NCG Committee's recommendation, and publicly disclose its decision regarding the tendered resignation and the rationale behind the decision within ninety (90) days from the date of the certification of the election results.

              In voting for the election of directors, each share has one vote for each position to be filled and there is no cumulative voting.

RECOMMENDATION OF BOARD OF DIRECTORS

              Our Board of Directors recommends that you vote FOR each of the director nominees.    The persons named as proxies will vote for the election of each of the nine nominees unless you specify otherwise. If any director nominee were to become unavailable prior to the Annual Meeting, your proxy would be voted for a substitute nominee designated by our Board or we would reduce the size of the Board.

SELECTION OF DIRECTOR NOMINEES

Director nominees are generally recommended to the Board by the NCG Committee for nomination by our Board and subsequent election by our stockholders. Director nominees may also be recommended byto the NCG Committee for appointment to our Board, with election by stockholders to follow at the next Annual Meeting.Board. Our Board believes that the backgrounds and qualifications of our directors, considered as a group, provide a mix of complementary experience, knowledge, and abilities that allowsenables our directors to effectively fulfill their oversight responsibilities.

In considering whether to recommend a candidate as a director nominee, the NCG Committee applies the criteria described in our Governance Policies,governance policies, including independence, integrity, unwaveringhigh personal and professional ethics, sound business judgment, integrity, and the ability and willingness to commit sufficient time to the Board. In evaluating the suitability of individual Board members, the NCG Committee takes into account many factors, including a general understanding of business development and strategy, risk management, finance, financial reporting, and other disciplines relevant to the success of a publicly-tradedpublicly traded company in the then-currentthen current business environment; understanding of our business and the issues affecting that business;it; relevant education and professional background; personal


Table accomplishment; and diversity. The NCG committee does not have a formal policy specifying how diversity of Contents

accomplishment;background and personal experience should be applied in identifying or evaluating director candidates, and a candidate’s background and personal experience, while important, does not necessarily outweigh other attributes or factors the NCG Committee considers in evaluating candidates. However, the Board of Directors is committed to identifying candidates with gender, racial and/or ethnic diversity. The NCG Committee does not assign specific weights to the criteria, and no particular criterion is necessarily applicable to all nominees.

In recommending candidates for election to the Board of Directors, the NCG Committee considers nominees recommended by directors, officers, stockholders, and others using the same criteria to evaluate all candidates. The NCG Committee reviews each candidate'scandidate’s qualifications, including whether athe candidate possesses any of the specific qualities and skills desirable in certain members of the Board of Directors. Evaluations of candidates generally involve a review of background materials,information, internal discussions, and interviews with selected candidates as appropriate. Upon selection of a qualified candidate, the NCG Committee recommends the candidate for consideration by the full Board. The Committee may engage consultants or third-party search firms to assist in identifying and evaluating potential nominees.

STOCKHOLDER SUBMISSION OF DIRECTOR NOMINEES

Stockholder Submission of Director
Stockholders may recommend director candidates by submitting the candidate's name,candidates’ names, together with his or her biographical information, professional experience and written consent to nomination,their qualifications, to NCG Committee Chair, c/o Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107. To be considered at the 20192025 Annual Meeting, stockholder nominations must comply with the notice procedures and other requirements of our bylaws as described under “Submission of Stockholder Items for 2025 Annual Meeting” in theMeeting and Voting Information section of this proxy statement under "Submissionstatement.

Tetra Tech 2024 Proxy Statement 23

Our Board of Stockholder Items for 2019 Annual Meeting." The NCG Committee considers stockholder nominees on the same basis as it considers all other nominees.

Directors

Director Qualifications

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DIRECTOR QUALIFICATIONS

              The qualifications

Qualifications that are particularly desirable for our directors to possess in order to provide oversight and stewardship of our companyCompany include those listed in the following:

table.
Desirable Director Qualifications
QualificationDescription



Qualification





Description





Value to Our Board and Stockholders



​ ​ ​ ​ ​ ​ 
Senior Leadership ExperienceService in a senior executive positionProvides us with valuable external perspectives with which to assess our operations, execute our strategies, mitigate related risks, and improve our policies and procedures.
​ ​ 
​  Industry and Technical ExpertiseExperience in consulting and engineering services that focus on water, the environment, infrastructure, resource management, energy and international developmentrelated servicesAllows us to better understand the needs of our clients in developing our business strategies as well as to evaluate acquisition and divestiture opportunities.
​ ​ Government Client Regulatory Experience
​  Government Client ExperienceService in a position that requires interaction with government clientsProvides us with experience and insight into working constructively with government agencies and administrators and addressing significant public policy and regulatory compliance issues in areas related to our business and operations.
​ ​ Business Development and M&A Experience
​  Business Development and Mergers and Acquisitions (M&A) ExperienceBackground in business development and in the analysis of proposed M&A transactionsProvides us with insight into developing and implementing strategies for growing our business through combinations with other organizations, including analyses of the "fit"“fit” of a proposed acquisition with our company'sCompany’s strategy, the valuation of the transaction, and the management plan for integration with existing operations.
​ ​ Financial Sophistication
​  Financial SophisticationUnderstanding of accounting, auditing, tax, banking, insurance, or investmentsHelps us oversee our accounting, financial reporting, and internal control processes,processes; manage our capital structure,structure; optimize capital allocation,allocation; and undertake significant transactions.
​ ​ Public Board Experience
​  Public Board ExperiencePrior or concurrent service on other SEC-reportingSEC reporting company boardsDemonstrates understanding of the extensive and complex oversight responsibilities of directors and helps reinforce management accountability for maximizing long-term stockholder value. Also provides insights into a variety of strategic planning, compensation, finance, and governance practices.
Innovation / Technology ExperienceDomain expertise and skill, technology/innovation, and practical experience with tech transformation and disruptionAllows us to better understand and anticipate technical trends, generate disruptive innovation, and extend and create new business models.
International Operations ExperienceExperience with global companies, especially those with operations in Australia, Canada and EuropeProvides us with insight into the conduct of global operations, including an understanding of diverse business environments and economic conditions and cultures and a broad perspective on global business opportunities.
Risk Oversight ExperiencePractical experience in risk governance, ERM framework, and knowledge/understanding of risk monitoring and mitigationHelps us understand ERM program structures as well as practices and policies designed to identify and manage risks and to properly align risk taking with overall governance and operations.
Talent Management / Compensation ExperiencePractical experience developing, managing, motivating, and compensating employeesProvides us with insight into cultivating an inclusive culture consistent with our values and purpose, providing an engaging work environment, attracting top talent, investing in our employees, supporting their career development, and remaining competitive in the marketplace.


Tetra Tech 2024 Proxy Statement 24

Our Board of Contents

Directors

The graph below shows the qualifications of our FY 2024 director nominees:

GRAPHIC

BOARD REFRESHMENT

nominees.

[MISSING IMAGE: bc_nominee-pn.jpg]
Board Refreshment
Our Governance Policiesgovernance policies reflect our belief that board refreshment is achieved through a variety of practices. In particular, the Board has set the maximum tenure for non-employee directors should not be subjectat 12 years, except that the maximum tenure is 15 years for directors whose service began prior to term limits. While term2014 to facilitate the transfer of institutional knowledge and provide for productive board refreshment upon adoption of the tenure requirement. Tenure limits couldserve to facilitate fresh ideas and viewpoints being consistently brought to the Board, we believe they are counter-balanced by the disadvantage of causing the loss of a director who over a period ofwhile still allowing sufficient time has developedfor directors to develop insight into our strategies, operations, and risks and continues to provide valuable contributions to Board deliberations. We believe that our decision not to establish term limits is consistent with the prevailing practice among companies in the S&P 1000. We recognize that certain governance stakeholders have suggested that longer-serving directors may have decreased independence and objectivity; however, we believe that an arbitrary decision to remove knowledgeable directors and the consistent oversight they bring weighs against strict restrictions on director tenure. Ultimately, it is our Board's responsibility to establish board refreshment policies, using its discretion in the best interest of our company and stockholders.

We have adopted the policies shown in the table below to facilitate refreshment of our Board and ensure that it continues to appropriately challenge our management.


POLICIES SUPPORTING BOARD REFRESHMENT

Policies Supporting Board Refreshment
PolicyDescription
Mandatory Director Resignation



Policy





Description



​ ​ ​ ​ 
Mandatory ResignationIncumbent directors who are not elected by a majority vote of the votes cast by our stockholders must promptly tender their resignation.resignation to the Board.
​ ​ Mandatory Retirement
​  RetirementThe Board has fixed the retirement age for directors at 75 (determined as of the Annual Meeting following the director'sdirector’s birthday). However, Mr. Grant has been exempted because of his special qualifications and experience, and the Board has waived this mandatory retirement requirement solely for him.
​ ​ Tenure LimitThe Board has set the maximum tenure for non-employee directors at 12 years, except that the maximum tenure is 15 years for directors whose service began prior to 2014.
Resignation Tendered Uponupon Retirement or Change in Principal EmploymentA directorDirectors who retiresretire from or changes his/herchange their principal occupation or business association must offer to tender his/hertheir resignation to the chair of the NCG Committee so that there is an opportunity for the Board, through the NCG Committee, to review the continued appropriateness of Board membership under the new circumstances.
​ ​ Overboarding
​  Over-BoardingWithout specific approval from the Board, no director may serve on the boards of more than three other public company boards.
companies.


Tetra Tech 2024 Proxy Statement 25

Our Board of Contents

Directors

The graph below shows the tenure of our FY 2024 independent director nominees:

GRAPHIC

DIRECTOR DIVERSITY

              As provided in our Governance Policies, we are committed to considering candidates for the Board regardless of gender, ethnicity and national origin. While diversity is a consideration, nominees are not chosen or excluded solely or primarily based on such basis. Rather, thenominees.

[MISSING IMAGE: tbl_tenure-pn.jpg]
Director Diversity
The NCG Committee focuses on skills, expertise, and background to complement the existing Board in light of the diverse and global nature of our businessesbusiness and operations. Women comprise more than half of our director nominees. Two of our director nominees identify as racial or ethnic minorities, and one of our director nominees identifies as LGBTQIA+.
[MISSING IMAGE: pc_directordiversity-pn.jpg]
Active Stockholder Engagement and Communication Policy
Governance Engagement
We value our stockholders’ opinions about our governance policies and practices and actively solicit input through our stockholder engagement program. In advance of the 2024 Annual Meeting, we proactively contacted our largest institutional stockholders, representing a majority of our then outstanding shares, to solicit their views on our corporate governance, executive compensation programs, and ESG. We welcome feedback on our Corporate Governance Program that this active and ongoing engagement with stockholders provides.
Contacting the Board
Stockholders may contact our Board, Chairman, Presiding Director, any committee or committee chair, or any other individual director concerning business related matters by writing to Board of Directors (or a particular subgroup or individual director), c/o Corporate Secretary, Tetra Tech, 3475 E. Foothill Boulevard, Pasadena, California 91107 or via email to TES.AskTheBoard@tetratech.com.
All such communications will be reviewed by the Secretary or their designee for the sole purpose of determining whether the contents represent a message to the Company’s directors. The two independentSecretary will forward copies of all correspondence that, in the opinion of the Secretary, deals with the functions of the Board or its committees or that they otherwise determine requires the attention of any member, group or committee of the Board. The Secretary will not forward junk mail, job inquiries, business solicitations, offensive or otherwise inappropriate materials.

Tetra Tech 2024 Proxy Statement 26

Item 1: Election of Directors
Item 1: Election of Directors
Our bylaws provide for a board of between five and 10 directors, appointedwith the exact number fixed from time to time by a resolution of our Board. The Board has fixed the number at eight directors, reducing to seven as of the end of the 2024 Annual Meeting. Each of the nominees is currently a member of our Board of Directors and was elected to our Board of Directors at the 2023 Annual Meeting of Stockholders.
Each director elected at the 2024 Annual Meeting will serve until our 2025 Annual Meeting and until their respective successors are duly elected and qualified or until his or her resignation or removal. Each of the nominees has consented to being named in 2013,this proxy statement and to continue serving if elected. If any nominee is unable or unwilling to stand for election or serve as a director if elected, the persons named as proxies may vote for a substitute nominee designated by our existing Board of Directors, or our Board may choose to reduce its size.
Vote Required
Our bylaws provide that each director nominee will be elected at the Annual Meeting if they receive a majority of the votes cast with respect to their election in an uncontested election like this one. Consequently, in order to be elected, a nominee must receive more votes “for” than “against” their election. Abstentions and broker non-votes will have no effect on the outcome of the vote.
Under Delaware law, if an incumbent director is not re-elected at a meeting of stockholders at which he or she stands for re-election, then the incumbent director continues to serve in office as a holdover director until his or her successor is elected. To address this “holdover” issue, should any of the nominees fail to receive the vote required to be elected in accordance with our bylaws, that director must promptly tender their resignation to the Board of Directors. In that event, the NCG Committee will make a recommendation to the Board as to whether to accept or reject the tendered resignation or to take another action. The Board will then act on the tendered resignation, taking into account the NCG Committee’s recommendation, and publicly disclose its decision regarding the tendered resignation and the independentrationale behind the decision within 90 days from the date of the certification of the election results.
In voting for the election of directors, each share has one vote for each position to be filled and there is no cumulative voting.
Recommendation of Board of Directors
Our Board of Directors recommends that you vote FOR each of the director appointed in 2016, are women.

2018 DIRECTOR NOMINEES

nominees. The following pages providepersons named as proxies will vote for the election of each of the seven nominees unless you specify otherwise.

2024 Director Nominees
This section provides information on each nominee for the Board of Directors for election at the 2024 Annual Meeting, including his or hertheir age, boardBoard leadership roles held, and business experience during at least the past five years. We also indicate the name of any other public company for which each nominee currently serves as a director. For these purposes, "public company" means one that is required to file reports withdirector or served as a director during the SEC.

              Presented below ispast five years.

The information regardingon each nominee's experience and qualifications thatnominee led our Board to the conclusion that he or shethey should serve as a director.director in light of the Company’s business and structure. We believe that each of these nominees has integrity and adheres to our high ethical standards. In addition, each nominee has demonstrated the ability to exercise sound judgment as well as a commitment to serving the long-term interests of our stockholders.


Tetra Tech 2024 Proxy Statement 27

Item 1: Election of Directors
Dan L. BatrackChairman and CEODirector since 2005
[MISSING IMAGE: ph_danbatrack-bw.jpg]
Experience

CEO and director since 2005; Chairman since 2008; President from 2008 to 2019

Joined Tetra Tech in 1980 and has served in numerous capacities, including arctic research scientist, deepwater oceanographic hydrographer, coastal hydrodynamic modeler, environmental data analyst, project and program manager, and President of the Engineering Division, and, in 2004, was appointed Chief Operating Officer

Established the firm’s strategic direction and focus on Leading with Science® to become the premier global consulting firm focused on water, environment, and sustainable infrastructure

Led research and engineering programs in locations in the Arctic and throughout South America, the Middle East, and the United States

Serves as corporate sponsor for several of our clients’ programs and remains engaged in our day-to-day operations
Age65



DAN L. BATRACK







​ 







GRAPHIC



Age 59



Director since November 2005



Attendance at Fiscal 2017 Board Meetings: 100%








Select Business Experience

Tetra Tech, Inc.

Chief Executive Officer and a director from November 2005 to present

Chairman from January 2008 to present

President from October 2008 to present

Joined Tetra Tech's predecessor in 1980; served in numerous roles of increasing responsibility at our company, including project scientist, project manager, operations manager, senior vice president, president of an operating unit and Chief Operating Officer

Managed complex programs for many small and Fortune 500 clients, both in the U.S. and internationally

Select

Skills and Qualifications

Senior leadership experience;leadership; industry and technical experience; government client regulatory experience; business development and M&A experience;&A; financial sophistication

sophistication; innovation/technology; international operations; risk oversight; talent management/compensation.

Nine years leading our company as Chairman, 12 years as Chief Executive Officer and nine years as President

Primary responsibility for our M&A strategy

Served as project manager on numerous government client projects

Member of Visitors Committee,

BA, Business Administration, University of Washington College of Engineering

Bachelor's degree in Business Administration from the University of Washington

Current Board Leadership Role

Chairman of the Board






Table of Contents


Gary R. BirkenbeuelIndependent


Director since 2018

HUGH M. GRANT







[MISSING IMAGE: ph_garyrbirken-bwlr.jpg]
​ ​ ​ 










GRAPHIC



Age 81


Director since January 2003


Independent


Attendance at Fiscal 2017 Board Meetings: 100%












Select Business
Experience

38

Retired after 37 years with Ernst & Young LLP (and its predecessor, Arthur Young & Company)

(E&Y)

Vice Chairman and

Former Regional Assurance Managing Partner, of the Western United States

E&Y, 2003-2017


Served as the audit partner in charge of several large publicmultinational publicly and privately held companies including thoseengaged in the engineering and constructionaerospace and defense, industries

Served on Ernst & Young's 15-member Management Committee for ten years

Serves as the Vice Chairmanentertainment, technology, and Chairmanmedia industries

Skills and Qualifications
Senior leadership; financial sophistication; audit committee financial expert; certified public accountant; risk oversight; talent management/compensation.

Visiting Professor, Claremont McKenna College

Director and chairman of the Audit Committee of Inglewood Park Cemetery since 1998

Select Skillsinvestment and Qualifications

Senior leadership experience; financial sophistication

audit committees, American Film Institute

Served on the Management Committee of Ernst & Young, and as the Vice Chairman and Regional Managing Partner of the Western United States, which had 2,000 employees and 19 offices

38 years of financial and risk management expertise gained through auditing public companies

"Audit committee financial expert" under SEC rules

Certified Public Accountant

Bachelor of Science degree in Business, with distinction, from the University of Kansas

Current Board Leadership Roles

Chair, Audit Committee
Member, Nominating and Corporate Governance Committee


BA, Economics, Claremont McKenna College






Age66
Current
Committees:

Table of Contents


Chair, Audit;
Member, NCG

Tetra Tech 2024 Proxy Statement 28

Item 1: Election of Directors


Prashant Gandhi

PATRICK C. HADEN



Independent



Director since 2022

[MISSING IMAGE: ph_prashantgandhi-bwlr.jpg]
​ ​ ​ 













GRAPHIC



Age 64


Director
Experience

Chief Business Officer of Melio Payments since December 1992


Independent


Other Public2021

Head of Digital Payments, JP Morgan Chase, 2017-2021

Partner and Global Chief Operating Officer, Digital Practice, McKinsey & Company, Board:
TCW Strategic Income Fund


Attendance at Fiscal 2017
Board Meetings: 100%
















Select Business Experience

President, Wilson Avenue Consulting, since July 2017

Advisor to the President, University of Southern California (USC), from July 2016 to June 2017

Athletic Director, USC, from August 2010 to June 2016

Director of TCW Funds, TCW Strategic Income Fund (a closed end mutual fund listed on the NYSE), TCW Liquid Alternative Fund and Met West Funds, and serves on various Board committees of these companies

Director of Auto Club of Southern California, and on the Audit/Finance and Investment Committees, since 2016

General Partner of Riordan, Lewis & Haden (RLH), a Los Angeles-based private equity firm, from 1987 to August 2010

Director of several portfolio companies during his tenure at RLH

Serves on several foundation Boards: Rose Hills, Fletcher Jones, Unihealth and Mayr.

Select 2000-2016

Skills and Qualifications

Senior leadership experience;leadership; business development and M&A experience;&A; financial sophistication; public board experience

innovation/technology; international operations; risk oversight; talent management/compensation.

Multiple roles at a major university, which provides significant senior leadership and management experience

Leadership at a private equity firm, which provides significant experience in finance and investment, and in M&A transactions

Director roles at several TCW funds, one

Advisory Board member, University of which is publicly listed

Minnesota’s School of Information & Decision Sciences

Service on other boards


BS, Chemical Engineering, Indian Institute of Technology Delhi

Rhodes Scholarship to Oxford University; degree in Economics


MS, Chemical Engineering, Kansas State University

Practicing attorney from 1982 to 1987

Current Board Leadership Roles

Member, Nominating and Corporate Governance Committee
Member, Compensation Committee


MBA, University of Chicago’s Booth School of Business








Age52

Table of Contents


Current
Committees:
Member, NCG;
Member, SPER



J. CHRISTOPHER LEWIS







​ ​ ​ ​ 










GRAPHIC



Age 61


Director since February 1988


Independent


Attendance at Fiscal 2017 Board Meetings: 100%












Select Business Experience

Managing Director (and co-founder) of RLH since 1982

Director of several privately-held companies: The Chartis Group, RGM Group, Bluewolf Group and Silverado Senior Living

Previously served as a director of two publicly-traded companies

Select Skills and Qualifications

Senior leadership experience; business development and M&A experience; financial sophistication

More than 35 years of leadership of a private equity firm and service as a director of several companies provides significant senior leadership, management, operational and financial experience

Private equity firm leadership provides significant experience in finance and investment, in evaluating new business opportunities, and in M&A transactions

"Audit committee financial expert" under SEC rules

Master's degree in Business Administration from the University of Southern California

Current Board Leadership Roles

Member, Audit Committee
Member, Compensation Committee







Joanne M. Maguire

Table of Contents


Independent, Presiding DirectorDirector since 2016



JOANNE M. MAGUIRE







[MISSING IMAGE: ph_maguirejoanne22-bw.jpg]
​ ​ ​ 
















GRAPHIC



Age 63


Experience

Presiding Director, since November 2016


Independent


Other Public Company Boards:

    CommScope, Inc.
    Visteon Corporation


Attendance at Fiscal 2017 Board Meetings: 100%




















Select Business Experience

February 2023

Served as Executive Vice President

EVP of Lockheed Martin Space, Systems Company (SSC), a provider of advanced-technology systems for national security, civil and commercial customers, from 2006 until retirement in 2013

2006-2013


Joined Lockheed Martin Corporation in 2003 and assumed leadership of SSC in 2006


Formerly with TRW'sTRW’s Space & Electronics sector (now part of Northrop Grumman), filling a range of progressively responsible positions from engineering analyst to Vice President and Deputy to the sector'ssector’s CEO

Member of the Board of Directors of Draper Laboratory

Select

Skills and Qualifications

Senior leadership experience;leadership; government client regulatory experience; industry and technical expertise; financial sophistication; risk oversight; corporate governance; public board experience

board; innovation/technology; talent management/ compensation.

Held senior leadership positions within a publicly traded company in the technology sector, working with government clients

These positions provide valuable experience, including strategic planning, operations, risk management

Chair, Nominating and corporate governance

Corporate Governance Committee, CommScope


Chair, Technology Committee, Member, Compensation Committee Visteon Corporation

Elected to the National Academy of Engineering in 2011

Bachelor's degree in

BS, Engineering, from Michigan State University and Master's degree in

MS, Engineering, from the University of California, Los Angeles

Concurrent service on two other public boards

Current Board Leadership Roles

Chair, Nominating and Corporate Governance Committee
Member, Strategic Planning and Enterprise Risk Committee











Age69
Current
Committees:
Chair, NCG,
Member, Compensation
Other Current
Public Boards:
CommScope, Inc.,
Visteon Corporation
Tetra Tech 2024 Proxy Statement 29

Item 1: Election of Directors
Christiana ObiayaIndependent


Director since 2023

KIMBERLY E. RITRIEVI







[MISSING IMAGE: ph_christianaobiaya-bwlr.jpg]
Experience

CEO and Director of Heliogen since February 2023; CFO 2021-2023; head of Executive Committee

CFO and Head of Strategy for Bechtel Energy, 2017-2021; leadership roles at Bechtel in finance; strategy; and project development, investment, and execution, 2010-2017

Prior to Bechtel, worked on renewable energy projects in Kenya and India, 2008-2009; engineer at a multinational consumer goods company, 2004-2008
Skills and Qualifications
Senior leadership; industry and technical expertise; government client regulatory; business development and M&A; financial sophistication; public board; innovation/technology; international operations; risk oversight; talent management/ compensation.

BS, Chemical Engineering, Massachusetts Institute of Technology (MIT)

MBA, MIT Sloan School of Management
​ ​ 






Age




GRAPHIC



Age 59


41
Current
Committees:
Member, Compensation;
Member, SPER
Other Current
Public Boards:
Heliogen, Inc.
Kimberly E. RitrieviIndependentDirector since November 2013


Independent


Attendance at Fiscal 2017 Board Meetings: 100%






[MISSING IMAGE: ph_kimberlyrit-bwlr.jpg]






Select Business
Experience


President of The Ritrievi Group LLC, advisingsince 2005

Advisor to technology and chemical companies on financial strategies,

2005-2018; private investor 2018-present

Co-Director of

Codirector, Americas Investment Research, at Goldman, Sachs & Co. from 2001 to 2004

Former, 2001-2004; Specialty Chemical Analyst, at Goldman, Sachs & Co., Credit Suisse First Boston, Lehman Brothers, and Paine Webber (now UBS Wealth Management)

Process

Skills and Qualifications
Senior leadership; business development engineer at ARCO Chemical

Serves as Vice Chair of the Dean's Advisory Board of the Harvard School of Dental Medicine since 2015, served as Chair of the Dean's Advisory Board from 2011 to 2015 and member since 2001

M&A; industry and technical expertise; financial sophistication; audit committee financial expert; international operations; public board; innovation/technology; risk oversight; talent management. Designated ESG expert.

Serves as Co-Chair of the

Princeton University School of Engineering and Applied Science Leadership Council since 2016 and member since 2000

Select Skills and Qualifications

Senior leadership experience; business development and M&A experience; industry and technical expertise; financial sophistication

Over 20 years of executive, management, analytical and operational experience at The Ritrievi Group and major investment banks

Master's degree in Management from theCouncil; Massachusetts Institute of Technology (MIT) Sandbox Funding Board; Wellesley Centers for Women Council of Advisors


Chair, Audit Committee, Mativ Holding, Inc.

Advisory Director, Intrinio

BS, Chemical Engineering, Princeton University

MS, Management, MIT Sloan School of Management

Doctorate in

ScD, Chemical Engineering, from MIT

"Audit committee financial expert" under SEC rules

Current Board Leadership Roles

Member, Audit Committee
Member, Strategic Planning and Enterprise Risk Committee







Age65
Current Committees:Member, Audit;
Chair, SPER
Other Current
Public Boards:
Mativ Holdings, Inc.
Tetra Tech 2024 Proxy Statement 30

Item 1: Election of Directors
Kirsten M. Volpi



ALBERT E. SMITH







​ ​ ​ ​ 
















GRAPHIC



Age 68


Director since May 2005


Independent


Other Public Company Board:
    Curtiss-Wright Corporation


Attendance at Fiscal 2017 Board Meetings: 100%




















Select Business Experience

Chairman of the Board of Tetra Tech, Inc. from March 2006 to January 2008, and Vice Chairman from September 2005 to March 2006

Executive Vice President of Lockheed Martin Corporation and head of its Integrated Systems & Solutions business from 2003 to 2004

Executive Vice President of Lockheed Martin's Space Systems Company from 1999 to 2003

Member of the U.S. Secretary of Defense's Defense Science Board from 2002 to 2005

Served on the Board of Trustees of Aerospace Corporation from 2005 to 2007

Worked for the U.S. Central Intelligence Agency, and received the Intelligence Medal of Merit

Select Skills and Qualifications

Senior leadership experience; government client experience; industry and technical expertise; financial sophistication; public board experience

Over 20 years of executive, management and operational experience, including leadership roles with Tetra Tech and at Lockheed Martin

Experience with government clients and requirements

Engineering degree from Northeastern University

Concurrent service on another public board

Current Board Leadership Roles

Presiding Director
Chair, Strategic Planning and Enterprise Risk Committee
Member, Nominating and Corporate Governance Committee











Director since 2013

Table of Contents


[MISSING IMAGE: ph_kirstenvolp-bwlr.jpg]



J. KENNETH THOMPSON







​ ​ ​ ​ 
















GRAPHIC



Age 66


Director since April 2007


Independent


Other Public Company Boards:
    Alaska Air Group Inc.
    Coeur Mining, Inc.
    Pioneer Natural Resources
    Company


Attendance at Fiscal 2017 Board Meetings: 100%




















Select Business
Experience

President/CEO

EVP, COO, and co-owner of Pacific Star Energy, LLC, a private energy investment firm in Alaska, since 2000

Managing Director of the Alaska Venture Capital Group LLC, a private oil and gas exploration firm, from 2004 to 2012

Executive Vice President of Atlantic Richfield Company's (ARCO) Asia-Pacific Region, leading the Asia-Pacific operating companies in Alaska, California, Indonesia, China and Singapore, from 1998 to 2000

Served in various technical and management roles at ARCO from 1974 to 2000, including head of ARCO's oil and gas research and technology center, and responsible for global technology strategy and energy technology transfer to more than 20 countries

Serves as Chairman of the Board of CDF Capital, a non-profit, since 2017

Select Skills and Qualifications

Senior leadership experience; industry and technical expertise; business development and M&A experience; financial sophistication; and public board experience

Various executive positions, including the role of CEO, provide leadership, risk management operations, strategic planning, engineering, environmental, safety and regulatory experience.

Expertise in mining and in oil and gas

Served on ARCO's team to assess and transition multi-billion dollar acquisitions

Served on ARCO's team to review monthly and quarterly financial statements before release to the Board and Audit Committee; also serves, or has served, on the audit committees of two public companies

Petroleum Engineering degree from Missouri University of Science & Technology

Concurrent service on three other public boards; Lead Director of Pioneer Natural Resources Company

Current Board Leadership Roles

Chair, Compensation Committee
Member, Strategic Planning and Enterprise Risk Committee












Table of Contents





KIRSTEN M. VOLPI







​ ​ ​ ​ 










GRAPHIC



Age 53


Director since July 2013


Independent


Attendance at Fiscal 2017 Board Meetings: 100%












Select Business Experience

Executive Vice President, Chief Operating Officer, Chief Financial Officer and Treasurer,CFO, Colorado School of Mines, from July 2013 to present, andsince 2013; Senior Vice President for Finance and Administration, Chief Financial OfficerCFO, and Treasurer, from August 2005 to August 2011

2005-2011


Chief Administrative Officer, U.S. Olympic Committee, from August 2011 to July 2013

2011-2013


Various financial management roles for Rensselaer Polytechnic Institute, the University of Colorado Foundation, and the American Water Works Association

Select Skills

kills and Qualifications

Senior leadership experience;leadership; financial expertise

Various executive positions provide leadership in financial and administrative matters

Extensive understanding of the preparation and analysis of financial statements

"Auditsophistication; audit committee financial expert" under SEC rules

expert; certified public accountant; international operations; risk oversight; talent management/compensation.

Certified Public Accountant

Bachelor's degree from

BS, Accounting, University of Colorado – Boulder

Current Board Leadership Roles

Member, Audit Committee
Member, Compensation Committee







Age59
Current
Committees:
Member, Audit;
Member, Compensation

Chairman Emeritus

Dr. Li-San Hwang has served as our honorary Chairman Emeritus since March 2006. As Chairman Emeritus, Dr. Hwang is invited to attend Board and Board committee meetings, but he does not have voting rights. Chairman Emeritus is an unpaid position; however, we reimburse Dr. Hwang for his attendance-related expenses.position. Dr. Hwang joined our predecessor in 1967 and led our acquisition of the Water Management Group of Tetra Tech Inc. from Honeywell Inc. in March 1988. He served as our Chief Executive OfficerCEO from our formation until November 2005. Dr. Hwang has served as an advisor to numerous government and professional society committees and has published extensively in the field of hydrodynamics. He is a graduate of the National Taiwan University, Michigan State University, and the California Institute of Technology, holding B.S., M.S.BS, MS, and Ph.D.PhD degrees, respectively, in Civil Engineering,civil engineering, specializing in water resources.


Director Compensation

Table of Contents

DIRECTOR COMPENSATION

The NCG Committee works with the independent compensation consultant, Meridian Compensation Partners, LLC (Meridian), to target non-employeenonemployee director compensation atwithin a competitive range of the median of our peer companies to support the recruitment and retention of our non-employeenonemployee directors. The majority of thiseach director’s compensation is delivered in equity to align director interests with those of our stockholders.

Fiscal 2017 Under our stock ownership guidelines, each nonemployee director must own shares having a value equal to at least five times the nonemployee director’s annual base cash retainer. Directors have five years from the date of their election to the Board to attain the required level of stock ownership.

FY 2023 Cash Compensation

During fiscal 2017,FY 2023, our non-employeenonemployee director cash compensation program consisted of the following:


ANNUAL NON-EMPLOYEE DIRECTOR CASH COMPENSATION

following elements.
Annual Nonemployee Director Cash Compensation
Cash retainer
$100,000Cash retainer$65,000
Additional cash retainer for Presiding Director$20,000
$35,000
Additional cash retainer for Audit Committee Chair$20,000
$20,000
Additional cash retainer for Compensation Committee Chair$15,000
$15,000
Additional cash retainer for NCG Committee Chair$10,000
$15,000
Additional cash retainer for SPER Committee Chair$15,000
Additional cash retainer for Strategic PlanningAudit Committee and Enterprise RiskCompensation Committee Chairmembership$10,000
$5,000
Additional fee per in-person or telephonic Board meeting attended$  2,000
or committee meetings in excess of eight
Additional fee per in-person or telephonic Audit Committee meeting attended$2,000
Additional fee per in-person or telephonic Compensation Committee, NCG Committee, or Strategic Planning and Enterprise Risk Committee meeting attended$  1,500


Tetra Tech 2024 Proxy Statement 31

Item 1: Election of Contents

Fiscal 2017Directors

FY 2023 Equity Compensation

During fiscal 2017,FY 2023, our non-employeenonemployee director equity compensation program consisted of an equity award based on a fixed dollar value of $150,000. The following table describes the following. All awards were granted on November 18, 2016. In each case, the number of shares is fixed,16, 2022.
PSU and not related to our stock price.

RSU Awards Granted
Type of Award
Type of Shares Underlying
Award





Number of
Shares
Underlying
Award




Description
​  Stock Option4,200Exercise price of $40.80 per share, the fair market value on the grant date; vests in full on the first anniversary if the director has not ceased to be a director prior to such date; and has a ten-year term. Vests immediately upon change in control and, upon the director's death, disability or retirement while a director, vests on the scheduled vesting date.
​ ​  (#)Description
Performance ShareStock Units (PSUs)1,800570Eligible for cliff-vestingRepresents target shares underlying the award. PSUs have a three-year performance period with cliff vesting on the third anniversary of the awardapplicable vesting date onand with the same terms as the PSUs awarded to our executive officers, subject to the achievement of the applicable performance goals. For additional information concerning PSU vesting, refer to theCompensation Discussion and Analysis section of this proxy statement. VestsPSUs vest immediately upon change in control or upon departure from the Board after serving 10 years or more, having served the full term for which the director was elected, and subject to achievement of the applicable performance criteria. Upon the director’s departure having served less than 10 years or upon the director's death or disability, or retirement while a director, vestsPSUs vest on a pro rata basis on the scheduled vesting date.date and subject to achievement of the applicable performance criteria. For additional information concerning PSU vesting, refer to the Compensation Discussion and Analysis section on page 37 of this proxy statement.
​ ​ Restricted Stock Units (RSUs)
​  Restricted Stock Units (RSUs)380900VestsVested on the first anniversary of the award dateNovember 18, 2023, if the director hashad not ceased to be a director prior to suchthat date. VestsRSUs vest immediately upon change in control or upon departure from the Board after serving 10 years or more and uponhaving served the director'sfull term for which the director was elected. Upon the director’s departure having served less than 10 years, RSUs vest on a pro rata basis. Upon the director’s death or disability, or retirement while a director, vests on the scheduled vesting date.
unvested RSUs are forfeited.

Table of Contents

Director Compensation Table

The following table provides information concerning the compensation for services of our non-employeenonemployee directors during fiscal 2017:


DIRECTOR COMPENSATION

FY 2023.
Direct Compensation by Director
Name1
Fees Earned or
Paid in Cash ($)
Option Awards ($)2
Stock Awards ($)3
Total ($)
Gary R. Birkenbeuel120,0000171,350291,350
Prashant Gandhi100,0000171,350271,350
Joanne M. Maguire155,0000171,350326,350
Christiana Obiaya105,0000149,350254,350
Kimberly E. Ritrievi120,0000171,350291,350
J. Kenneth Thompson115,0000171,350286,350
Kirsten M. Volpi110,0000171,350281,350

Name 



Fees Earned
or Paid In
Cash ($)(1)
 




Option
Awards ($)(2)
 



PSU Awards
($)(3)
 



RSU Awards
($)(4)
 



Total ($)  

Hugh M. Grant

  121,000  51,870  87,048  36,720  296,638 

Patrick C. Haden

  94,500  51,870  87,048  36,720  270,138 

J. Christopher Lewis

  102,500  51,870  87,048  36,720  278,138 

Joanne M. Maguire

  120,657  141,390  87,048  36,720  385,815 

Kimberly E. Ritrievi

  96,000  51,870  87,048  36,720  271,638 

Albert E. Smith

  122,500  51,870  87,048  36,720  298,138 

J. Kenneth Thompson

  106,500  51,870  87,048  36,720  282,138 

Kirsten M. Volpi

  100,500  51,870  87,048  36,720  276,138 

(1)
1Mr. Batrack does not appear in the table because he received compensation as our CEO and does not receive any additional compensation as director.
(2)
The
2 No stock options were granted to nonemployee directors in FY 2023. For information regarding the number of stock options held by each nonemployee director as of October 1, 2023, see the Stock Options Outstanding (#) column in the Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director table below.
3 $111,754 of the amounts in the OptionStock Awards column represent the aggregate grant date fair values, without adjustment for forfeitures, computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718 (FASB ASC Topic 718), of stock option awards. The grant date fair value of the stock option awards granted on November 18, 2016 to each non-employee director was $12.35 per share. The grant date fair value of the stock option award granted on November 6, 2016 to Ms. Maguire upon her election as a director was $11.19 per share. There can be no assurancePSUs that these grant date fair values will ever be realized by the non-employee directors. For information regarding the number of stock options held by each non-employee director as of October 1, 2017, see the column "Stock Options Outstanding" in the table below.
(3)
The amounts in the PSU Awards column represent the aggregate grant date fair values, without adjustment for forfeitures, which are payable at the end of a three-year performance period provided that the performance objectives are achieved as of the end of the period. The actual number of shares issued can range from 0% to 200% of the target shares at the time of grant. The performance objectives that determine the number of shares that may be earned for the PSUs were (i) as to 50% of the award, growth in earnings per share, which is a performance condition under FASB ASC Topic 718, and (ii) as to 50% of the award, total shareholderstockholder return (TSR), which is a market condition under FASB ASC Topic 718, relative to the TSR of (A) 1716 companies objectively determined based on GICS code and revenue size (25% of award) and (B) the S&P 1000 (25% of award), in each case computed over the three-year performance period. The performance condition component of the fair value of PSUs was determined based on the fair market value of our common stock on the date of grant. The market condition component of the fair value of the PSUs was determined as of the date of grant using the Monte-CarloMonte Carlo simulation method, which utilizesuses multiple input variables to estimate the probability of meeting the performance objectives established for the award, including the expected volatility of our stock price and other assumptions appropriate for determining fair value. Based on these computations, the grant date fair values of the performance condition-based PSU awards and the market condition-based PSU awards granted on November 18, 201616, 2022, to each non-employeenonemployee director on that date were $40.80$156.83 and $55.92$235.29 per share, respectively. The maximum grant date fair value of the PSU awards in FY 2023 (200% vesting) was $223,508 for each of the

Tetra Tech 2024 Proxy Statement 32

Item 1: Election of Directors
nonemployee directors. There can be no assurance that these grant date fair values will ever be realized by the non-employeenonemployee directors. For information regarding the number of unvested performance shares and PSUs held by each non-employeenonemployee director as of October 1, 2017,2023, see the column "Unvested Performance Shares andUnvested PSUs Outstanding"Outstanding column in the table below.
(4)
The $59,595 of the amounts in the RSUStock Awards column represent the aggregate grant date fair values, computed in accordance with FASB ASC Topic 718, of RSU awards. The grant date fair value of these awards is calculated using the closing price of our common stock on the grant date as if these awards were vested and issued on the grant date. The grant date fair value of the RSU awards granted on November 18, 201616, 2022, to each non-employeenonemployee director was $40.80$156.83 per share. There can be no assurance that these grant date fair values will ever be realized by the non-employeenonemployee directors. For information regarding the number of unvested RSUs held by each

Table of Contents

    non-employee nonemployee director as of October 1, 2017,2023, see the column "UnvestedUnvested RSUs Outstanding"Outstanding column in the following table.

Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director table below.

Each of the non-employeenonemployee directors owned the following number of nonqualified stock options, unvested performance shares and PSUs, and unvested RSUs as of October 1, 2017.

2023.
Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director
NameStock Options
Outstanding (#)
Unvested PSUs
Outstanding (#)
Unvested RSUs
Outstanding (#)
Mr. Birkenbeuel2431,663380
Mr. Gandhi01,105380
Ms. Maguire16,4001,633380
Ms. Obiaya0506337
Dr. Ritrievi01,663380
Mr. Thompson8,4001,663380
Ms. Volpi6,2001,663380

Tetra Tech 2024 Proxy Statement 33

Item 2: Advisory Vote to Approve Our Named Executive Officers’ Compensation

Name 



Stock Options
Outstanding (#)
 



Unvested
Performance
Shares and PSUs
Outstanding (#)
 





Unvested RSUs
Outstanding (#)
 
 

Mr. Grant

  61,000  5,400  900 

Mr. Haden

  29,000  5,400  900 

Mr. Lewis

  61,000  5,400  900 

Ms. Maguire

  12,200  1,800  900 

Dr. Ritrievi

  24,800  5,400  900 

Mr. Smith

  29,000  5,400  900 

Mr. Thompson

  53,000  5,400  900 

Ms. Volpi

  24,800  5,400  900 
Item 2: Advisory Vote to Approve Our Named Executive Officers’ Compensation

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ITEM 2 – ADVISORY VOTE TO APPROVE EXECUTIVE COMPENSATION

Our Board has determined to hold annual say-on-pay“say on pay” votes, andwhich ask stockholders to vote on the compensation of our stockholders voted in favor of annual say-on-pay votes at our 2017 Annual Meeting.named executive officers (NEOs). Our stockholders are being asked to vote on the following resolution:

RESOLVED, that our stockholders approve, on an advisory basis, the compensation of our Named Executive Officers, as described in theCompensation Discussion and Analysis andExecutive Compensation Tables sections of our 20182024 proxy statement.

RECOMMENDATION OF BOARD OF DIRECTORS

Vote Required
Approval of this advisory vote requires the affirmative vote of a majority of shares of common stock present or represented and entitled to vote on the proposal at the 2024 Annual Meeting. Abstentions will have the same effect as a vote “AGAINST” the proposal. Broker non-votes will have no effect on the outcome of the advisory vote.
Recommendation of Board of Directors
The Compensation Committee considered feedback from stockholders regarding our executive compensation program and has previously made significant changes to ourthe program to both address suggestions made by our stockholders and more closely align our compensation program with our current financial position and business strategies. YourOur Board of Directors recommends that you vote FOR approval, on an advisory basis, of our named executive compensation.officers’ compensation. Properly dated and signed proxies will be so voted unless stockholders specify otherwise.

MEANING OF ADVISORY VOTE

Meaning of Advisory Vote
The advisory vote is a vote to approve the compensation of our Named Executive Officers (NEOs),NEOs, as described in theCompensation Discussion and Analysis section on page 37 andExecutive Compensation Tables sections section on page 61 of this proxy statement. It is not a vote on our general compensation policies or any specific element thereof, the compensation of our non-employeenonemployee directors, or our program features designed to prevent excessive risk-takingrisk taking as described inRisks Associated with Compensation Policies and Practices.

Practices section on page 22 of this proxy statement.

The results of the advisory vote are not binding on our Board. However, inIn accordance with SEC regulations, however, the Compensation Committee will disclose the extent to which it takes into account the results of the vote in theCompensation Discussion and Analysis section of our 20192025 proxy statement. We remain committed to continued engagement with our stockholders to solicit and consider their viewpoints and discuss why we believe our executive compensation program properly aligns with our strategies and incents our executives to achieve strong, long-term operating and financial performance for our stockholders.


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COMPENSATION DISCUSSION AND ANALYSIS1
[MISSING IMAGE: ic_water-pn.jpg]

              This


Tetra Tech 2024 Proxy Statement 34

Compensation Discussion and Analysis
Compensation Discussion and Analysis
This compensation discussion and analysis (CD&A) provides an overview and analysis of the principles and practices underlying our executive compensation program and the decisions made by the Compensation Committee related to fiscal 2017 compensation.

              In thisFY 2023 compensation for our Named Executive Officers.

This CD&A and theExecutive Compensation Tables section on page 61 of this proxy statement we provide compensation information for our NEOs for fiscal 2017,FY 2023, who are identified below:


FISCAL 2017 NAMED EXECUTIVE OFFICERS

in the table below.
FY 2023 Named Executive Officers
NameTitle
Years in
Position at FYE
20231
Years at Tetra
Tech at
FYE 2023
Dan L. BatrackChairman, CEO1843
Steven M. BurdickEVP, CFO1220
Leslie L. ShoemakerEVP, Chief Sustainability and Leadership Development Officer132
Preston HopsonSVP, General Counsel, and Secretary66
Roger R. ArgusSVP and President, Government Services Group (GSG)630
  Name
 Title
 Years in
Position
at
Fiscal
2017
Year-
End







 Years at
Tetra
Tech at
Fiscal
2017
Year-
End







  Dan L. Batrack   Chairman, Chief Executive Officer and President   12   37  
  Steven M. Burdick   Executive Vice President and Chief Financial Officer   6   14  
  Ronald J. Chu*   Executive Vice President and President of Resource Management and Energy (RME)   8   19  
  Leslie L. Shoemaker   Executive Vice President and President of Water, Environment and Infrastructure (WEI)   2   26  
  Janis B. Salin**   Senior Vice President, General Counsel and Secretary   15   15  
1 FYE 2023 was October 1, 2023.
*
Retired from his role as an executive officer effective November 6, 2017 and retired from the company on December 15, 2017.
**
Retired effective January 22, 2018.

EXECUTIVE SUMMARY

Fiscal 2017FY 2023 Performance Highlights2

              Summary.Summary

Tetra Tech's fiscal 2017Tech’s FY 2023 operating results reflected a significant improvementwere strong and demonstrated increased performance compared to fiscal 2016,FY 2022, which was itself a year of strong operational and financial performance. In FY 2023 we achieved record-highs inrecord annual results with all-time highs for revenue, operating income, earnings, adjusted EBITDA, and EPS.cash flow. Our focus on providing clients with high-end differentiated consulting and engineering services primarily in the water, environment and infrastructure markets, has resulted in increased margins and reduced risk in our business.


1
This CD&A contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties, which could cause actual results to differ materially from the results, performance or achievements expressed or implied thereby. For a detailed discussion of these risks, see Part I, Item 1A. "Risk Factors" and Part II, Item 7. "Management's Discussion and Analysis of Financial Condition and Results of Operations" in our fiscal year 2017 Annual Report on Form 10-K, filed on November 20, 2017
We ended FY 2023 with the SEC (2017 Annual Report). Stockholders should note that statements contained in this CD&A regarding our company and business group performance targets and goals should not be interpreted as management's expectations, estimates of results, or other guidance.
2
For complete information regarding our fiscal 2017 performance, see "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our audited consolidated financial statements and notes thereto contained in our 2017 Annual Report.

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              Our fiscal 2017 revenue growth was generally consistent with our annual operating plan, and resulted from broad-based contract wins. The revenue growth was led by our U.S. federal government business, which increased 15% compared to fiscal 2016, and our U.S. state and local government business, which increased 14% compared to fiscal 2016. We began fiscal 2018 withan authorized and funded backlog that reached ananother all-time high in the fourth quarter of fiscal 2017.

              The following table presents highlightsapproximately $4.8 billion.

Highlights of our fiscal 2017FY 2023 results of operations compared to fiscal 2016, as reported in our FY 2023 Annual Report on Form 10-K for fiscal year 2017are noted in the table below.
FY 2023 Highlights
($ in millions, except EPS
and fiscal year 2016, respectively:

percentages)
$vs. FY 2022
Revenue$4,523+29%
Cash from Operations$368+10%
EPS$5.10+5%
Backlog$4,790+28%

 

 

Results of Operations
($ in millions, except EPS)



 

     Fiscal 2017
 Fiscal 2016
 Fiscal 2017 vs.
Fiscal 2016


 

 

Revenue

   $2,753   $2,583   +7%  

 

 

Operating Income

   $183   $136   +35%  

 

 

EPS

   $2.04   $1.42   +44%  

 

 

Cash Flow

   $138   $142   –3%  

 

 

Backlog

   $2,541   $2,379   +7%  

Disciplined Capital Allocation

We achieved these results while maintaining a healthy balance sheet and continuing the disciplined execution of our capital allocation strategy. Over the last three years, we have returned $360$398 million to our stockholders as shown below, which represents an annual stockholder return of one-third of our free cash flow.through dividends and stock repurchases. In fiscal 2017,FY 2023, we returned $122$52 million to our stockholders by

      repurchasing approximately 2.3 million shares at an aggregate cost of $100 million, and

      paying an aggregate dividend of $.38$0.98 per share at an aggregate cost of $22 million.

share. We have paid quarterly dividends since April 2014 and increased our dividend from $.07 at inception to $.10$0.26 per share in April 2017. Our goal for the dividend program is to provide an annual return of approximately 1% to our stockholders.

December 2023, a 271% increase over this period.

Tetra Tech 2024 Proxy Statement 35

Compensation Discussion and Analysis
GRAPHICGRAPHIC

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Strong Stock Price Performance

Our strong annual total stockholder return (TSR) of 32% in fiscal 2017 contributed toTSR for our cumulative three-year TSR of 91% forwas 70% and our cumulative five-year TSR was 130%. TSR measures the fiscal 2015 through fiscal 2017 period.return we have provided our stockholders, including stock price appreciation and dividends paid (assuming reinvestment thereof). We compare our TSR to the S&P 1000 and our TSR peer group (listed on p. 52page 51 of this proxy statement), and for purposes of our LTI program, as more fully explained below. We outperformed both in fiscal 2017 andmarket comparisons over the cumulative three-year period. TSR measures the return that we have provided our stockholders, including stock price appreciationperiod and dividends paid (assuming reinvestment thereof).


One- and Three-Year TSR

five-year period.
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[MISSING IMAGE: bc_5yrtsr-pn.jpg]

Tetra Tech 2024 Proxy Statement 36

Compensation Discussion and Analysis
GRAPHICGRAPHIC
Strong Compensation Governance Practices

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STRONG COMPENSATION GOVERNANCE PRACTICES

Our executive compensation program incorporates what we believe are best practices, as shown in the following best practices,table, which we believe ensure that the program serves the long-term interests of our stockholders.

Policy or Best Practice
Policy or Best
Practice


Description and Benefit to Our Stockholders
Majority of Compensation Performance-Based
PAY FOR PERFORMANCE
​  Majority of Compensation Performance-BasedFor fiscal 2017, 82%FY 2023, 87% of our CEO'sCEO’s target TDC,total direct compensation (TDC) (base salary + annual cash incentive opportunity + long-term equity incentive opportunity) and an average of 64%71% of our NEOs'NEOs’ target TDC was at-risk (all compensation components other than base salary). Further, 67%60% of our CEO'sCEO’s target TDC and an average of 54%52% of our other NEOs'NEOs’ target TDC was performance-based (AIP award options and PSUs).
​ ​ 
Median TargetingTDC (base salary + annual cash incentive opportunity + long-term equity incentive opportunity) and the components thereof are targeted atto be within a competitive range of the median of companies similar in size, scope, and complexity, givingwith variability based on various consideration tosuch as responsibilities, individual performance, tenure, retention, succession, and market factors.
​ ​  Pay decisions are not formulaic.
Capped Annual IncentiveAnnual cash incentive compensation is based primarily on our achievement of performance objectives in the categories of revenue, operating income, cash flow from operating activities, and backlog, with consideration for individual performance, with awards capped atranging from 0% to a cap of 200% of target.
​ ​ 
Majority Long-Term Equity Incentive CompensationThe majority of our equity-based incentive awards emphasize our long-term performance, with PSUs cliff-vestingcliff vesting at the end of three years, subject to achievement of the applicable performance goals. Equity compensation aligns NEO interests with stockholder interests by delivering compensation dependent on our long-term performance and stockholder value creation.
​ ​ Rigorous Goal Setting Process
Rigorous Goal-Setting ProcessAnnual review and approval are completed by the Compensation Committee of the performance goals for companythe Company (Corporate) and for the RME and WEIour business groups. The performance factor used to determine AIP awards is increased or decreased based upon the growth level of the targets from the prior fiscal year.
No Employment Agreements

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Policy or Best
Practice


Description and Benefit to Our Stockholders
BEST PRACTICES
​  No Employment AgreementsOur NEOs are employed at will, and they have no special severance benefits in the absence of a change in control.
​ ​ Stock Ownership Guidelines
​  Stock Ownership GuidelinesOur NEOs are required to obtain and maintain shares having a value equal to the lesser of (i) at least 2x to 6x base salary (based on position) or (ii) a fixed number of shares based on position.. All of our NEOs are in compliance with our stock ownership guidelines.
​ ​ No Hedging or Pledging
No Hedging or PledgingOur insider trading policy prohibits our directors and officers from hedging or pledging our common stock, and all of our NEOs are in compliance with thethat policy.
​ ​ Clawback Policy
​  Clawback PolicyIncentive compensation is subject toOur clawback ifpolicy provides that in the event we are required to prepare an accounting restatement, due to material noncompliancewe will recover, in accordance with the terms of the policy, compensation received after its effective date by any current or former executive officer that is based wholly or in part upon the attainment of a financial reporting requirements under the securities laws.measure.
​ ​ No Excise Tax Gross Ups
​  No Excise Tax
Gross Ups

We do not gross-upprovide excise tax gross up payments received in connection with a change in control for excise taxes.control.
​ ​ Double Trigger Equity Vesting
​  Double Trigger
Equity Vesting

No equity awards will be accelerated in connection with a change in control unless the NEO'sNEO’s employment is terminated without cause or the NEO terminates employment for good reason within two years thereof.
​ ​ 
​  No Repricing/Exchange of Underwater Stock OptionsOur equity incentive planEquity Incentive Plan prohibits the repricing/exchange of underwater options without stockholder approval.
​ ​ Limited Perquisites
​  Limited PerquisitesOur NEOs receive limited capped reimbursements for vehicle use, financial planning, tax planning, memberships, and annual physical examinations. These reimbursements are not subject to any tax gross-up.gross up.
Independent Oversight
STRONG GOVERNANCE
​  Independent OversightThe Compensation Committee is comprised solely of independent directors.
​ ​ Independent Expert Advice
​  Independent Expert AdviceMeridian, Compensation Partners (Meridian), which has been determined by the Compensation Committee to be independent and free of conflicts of interest, provides the Committee with expert executive compensation advice. Meridian was selected to acthas served as the independent advisor insince January 2016.


Tetra Tech 2024 Proxy Statement 37

TABLE OF CONTENTS 2017 SAY ON PAY VOTE AND EXECUTIVE COMPENSATION PROGRAM

Compensation Discussion and Analysis
2023 Say on Pay Vote and Executive Compensation Program
At the 20172023 Annual Meeting, approximately 90%95% of our stockholdersvotes cast approved our fiscal 2016FY 2022 executive compensation. In recent years, we have takencompensation program. It is our practice to take stockholder feedback into consideration as we have discusseddiscuss and implemented ourimplement compensation design changes. During fiscal 2017,FY 2023, the Compensation Committee reviewed best practices for executive compensation and evaluated the vote results at the 20172023 Annual Meeting and the results of our ongoing stockholder outreach program. Telephone conferences with our investors were attended by members of management in our law,legal, investor relations, and executive compensation functions. The feedback was subsequently reported to the Compensation Committee, and the Compensation Committee was able to develop a clear understanding of stockholder views. As a result, the Compensation Committee determined that no additional changes to our executive compensation program were warranted in fiscal 2017. The Compensation Committee remains committed to the ongoing evaluation of our executive compensation program and adjustments to this program to reflect feedback received from stockholders.


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Stockholder Engagement

Our ongoing engagement program begins in February of each year, following the filing of our proxy statement in late January. After we file our proxy statement with the SEC, we reach out to our largest investors (generally representing 50 -50% to 70% of our shares outstanding as of the record date), sharing these materials and offering a conversation to discuss our executive compensation and answer questions. On the day of the 2024 Annual Meeting, we discuss preliminary vote results with our Board and follow up with Board committees in the spring with a more detailed analysis of actual results, including feedback from investors and views of proxy advisory firms. In the fall, we again reach out to our largest investors to discuss executive compensation to hear what issues are important to our stockholders. In the winter, as we prepare for the following proxy season, we review the feedback from our fall outreach effort with management and our Board and consider whether any changes to our executive compensation program are advisable. We also keep investor feedback in mind as we prepare our next proxy statement by enhancing or clarifying our disclosure as appropriate.

Following the 2017 say-on-pay2023 say on pay vote, as part of our stockholder outreach program, we proactively contacted our largest institutional stockholders, representing approximately 60% of our outstanding shares as of the record date for the 2017 meeting,2023 Annual Meeting, to solicit their views on our executive compensation program and make directors and management available to answer questions orand address concerns. As a result of this effort, we engaged in telephonic discussions with stockholders representing approximately 50% of our then-outstanding shares. Additionally, our senior management team, including our CEO and CFO, regularly engage in meaningful dialogue with our stockholders through our quarterly earnings calls and other channels forof communication.

[MISSING IMAGE: tbl_outreach-pn.jpg]

Tetra Tech 2024 Proxy Statement 38

TABLE OF CONTENTS
Stockholder Outreach Cycle

GRAPHIC

OVERVIEW OF PAY PHILOSOPHY AND EXECUTIVE COMPENSATION COMPONENTS

Compensation Discussion and Analysis
Pay Philosophy and Executive Compensation Components
We believe in a "paypay for performance"performance compensation program in which a majority of the compensation is tied to our success in meeting both predetermined performance objectives and creating


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long-term stockholder value. The objective of this strategy is to motivate our executives to achieve our annual and long-term financial goals, align with stockholders, and recognize the executives'executives’ contributions in delivering strong corporate and/or business group performance. The Compensation Committee implements this philosophy and provides incentives to our executives by following three key principles:


Positioning target TDCtotal direct compensation (TDC) and each component thereof at approximately market median and thewith additional consideration given to various factors as discussed previously; failure to achieve financial objectives and create stockholder value should directly impact TDC relative to market median compensation;

compensation

Aligning our annual incentive awards with our annual operating planAOP and key financial and strategic objectives, thatwhich are predetermined and objectively measurable; and

measurable

Rewarding long-term performance using metrics such as EPS growth and relative TSR, which focusfocuses executives on consistent and sustainable stockholder value creation.creation
[MISSING IMAGE: fc_aip-pn.jpg]

The Compensation Committee targets TDC for NEOs atreferences the median TDC of companies similar in size, scope, and complexity with which we compete for executive talent, giving consideration toand then further considers responsibilities, individual performance, tenure, retention, company performance, succession planning, and market factors.factors for each executive to make final pay decisions. The Committee believes this varied positioning and approach is appropriate given our business portfolio mix, the diversity of our services, and the global nature of our operations, which require our executives to have a wide range of business leadership experience and skills.

Our incentive compensation for fiscal 2017FY 2023 consisted of a target award under ourthe AIP and LTI awards. The AIP award payouts were based on our performance against performance goals established by the Compensation Committee in November 20162022 for gross revenue, operating income, cash flow, and backlog. The AIP rewards NEOs based on corporate and/or business group and/or division performance as well as individual contributions to motivate the NEOs and align their compensation with stockholder interests. Both our AIP and our PSU awards under our LTI program provide upside opportunity for exceeding performance targets and downside risk, including forfeiture of PSUs and no payout under our AIP for failing to achieve predetermined performance targets. Our compensation is aligned with performance, and our ability to exceed or failure to achieve our performance targets would directly impactimpacts payments to our NEOs and their compensation relative to the market median.

The following graphic illustrates the components of our executive compensation program.


Tetra Tech 2024 Proxy Statement 39

Compensation Discussion and Analysis
Components of Annual and Long-termLong-Term Compensation

GRAPHIC


[MISSING IMAGE: pc_annual-pn.jpg]

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As

In FY 2023, as shown in the following graph, in fiscal 2017, 82%graphic, 87% of our CEO'sCEO’s target TDC and an average of 64%71% of our other NEOs'NEOs’ target TDC was at-riskat risk (all compensation components other than base salary). Further, 67%60% of our CEO'sCEO’s target TDC and an average of 54%52% of our other NEOs'NEOs’ target TDC was performance-basedperformance based (AIP award options and PSUs):

.


Tetra Tech 2024 Proxy Statement 40

Compensation Discussion and Analysis
FY 2023 NEO Target TDC Mix

GRAPHIC

[MISSING IMAGE: bc_trgettdc-pn.jpg]
[MISSING IMAGE: tbl_ceoneo-pn.jpg]

CEO'S 2017 TARGET TDC: 67% PERFORMANCE-BASED

AVERAGE OF OTHER NEOS' TARGET TDC: 54% PERFORMANCE-BASED

Summary of Compensation Decisions for FY 2023

SUMMARY OF COMPENSATION DECISIONS FOR FISCAL 2017

The key elements of our fiscal 2017FY 2023 NEO target TDC are shown in the following table. While we provide consistent, market-competitive total direct compensationmarket competitive TDC opportunities for our NEOs, the actual compensation they realize varies year-to-yearyear to year based on our performance.

Our CEO is not involved in the decisions regarding his own compensation, which areis determined by the Compensation Committee meeting in an executive session with consultation from Meridian.



Table of Contents


FISCAL 2017 TDC

Tetra Tech 2024 Proxy Statement 41

Compensation Discussion and Analysis
FY 2023 NEO TDC
ComponentPurpose
Component
Description
Decisions Impacting Fiscal 2017
FY 2023 Executive Compensation


Fixed
Base Salary
FIXED
​  Base SalaryProvides fixed, marketmarket- competitive monthly income for performing daily responsibilities


The Committee increased the CEO'sCEO’s base salary by 3%2.1% in fiscal 2017FY 2023 to reflect prior year performance, tenure, and theoverall market median. He had not received acompetitive base salary increase since fiscal 2014.

pay


The Committee adjusted certain NEO base salaries to reflect prior-yearprior year performance or position their salarysalaries at or around the market median, with increases ranging from 3%approximately 0% to 8%.

7%
Performance-Based Cash
AIP Award
PERFORMANCE-BASED CASH
​  AIP AwardProvides variable, cash-based incentive to motivate our executives annually to grow revenue, increase profitability, deliver strong cash flow, and replenish backlog consistent with our annual operating plan (AOP)AOP financial objectives

AIP opportunity is based on market survey data and independent consultant advice; financial modifier based on corporate or business group performance; and individual modifier based on defined objectives

Maximum

Target bonus opportunity, as a percentage of base salary, was 240%150% for the CEO, 150%80% for Executive Vice Presidents,EVPs, and 100%75% for Senior Vice Presidents, which representsthe general counsel and the SVPs with group or division president roles, with the bonus opportunity ranging from 0% to a maximum of 200% of each executive'sexecutive’s target bonus opportunity.

opportunity


The corporate and business group performance factor (CPF) has a range of 0 to 2.0, with a target of 1.0 based on achievement of four AOP targets (gross revenue,(revenue, operating income, cash flow, and backlog).


The Committee may make limited adjustments to AIP payments forbased on individual performance factors (IPFs). No adjustment was made for fiscal 2017.

and contributions


Minimum (threshold), target, and maximum performance criteria and payouts were established for each metric, with payout at 0% of target below threshold performance, 50% of target at threshold, 100% of target at target, and 200% of target at maximum.

maximum
Long-Term Incentives
PSUs
RSUs

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LONG-TERM INCENTIVES
​  PSUs
RSUs
Stock Options


ProvidesProvide variable equity-based incentive compensation to enhance the alignment of our executives'executives’ interests with stockholder interests and drive long-term value creation

Provide LTI opportunity, including award vehicles,vehicle selections, performance criteria and weightings based on market survey data, our pay philosophy, and independent consultant recommendations


For fiscal 2017, there was no change toFY 2023, the value of the target LTI opportunities for the CEO and one NEO. The value of other NEOs' target LTI opportunities wasthe SVPs were adjusted to target the market median.

median while also considering internal equity, retention, and individual performance and role, among other factors


PSUs have a three-year performance period with cliff vesting, subject to achievement of the applicable performance goals; vesting is determined at 50% by EPS growth and 50% by relative TSR:


EPS based vesting ranges from 0% for less than 5%2% average annual EPS growth to 200% for greater than or equal to average annual 35%16% EPS growth.

growth


TSR based vesting ranges from 0% if our TSR is less than the 30th25th percentile of the TSR peer groupgroups to 200% if our TSR is at the 90th75th or greaterhigher percentile of the TSR peer group.

groups

Target LTI opportunity set at market median, with TSR performance at 50th percentile of the TSR peer group. TSR vesting at 100% would only result in payment at market median. If TSR performance is less than 50th percentile, vesting would be appropriately below market median.


RSUs have time-based vesting at the rate of 25% per year, subject to the holder'sholder’s continuous employment by us through the applicable vesting date.

Stock options have time-based vesting at the rate of 25% per year, subject to the holder's continuous employment by us through the applicable vesting date.

date

In addition to these primary elements of our executive compensation program, we also provide our NEOs with limited perquisites and benefits.


Tablebenefits, as specified in the Strong Compensation Governance Practices section on page 38 of Contents

ASSESSMENT OF PAY FOR PERFORMANCE

this proxy statement.

Assessment of Pay for Performance
Our Compensation Committee designed the executive compensation program to reflect its philosophy that a majority of compensation should be tied to our success in meeting predetermined performance objectives, the achievement of which should positively influence our stock price. The objective is to motivate the executives to achieve these annual and long-term financial goals in order to deliver consistent and sustainable return to our stockholders. As indicated below, for the period fiscal 2015 through fiscal 2017, our CEO reported compensation increased 20%
Discussion of Compensation Components and on average, our other NEOs reported compensation increased 27%, compared to the 91% increase in our TSR performance over the same period.


Change in ReportedDecisions Impacting FY 2023 Compensation Compared to Three-Year Cumulative TSR
Fiscal 2015 through Fiscal 2017

GRAPHIC

DISCUSSION OF COMPENSATION COMPONENTS AND DECISIONS IMPACTING FISCAL 2017 COMPENSATION

The Compensation Committee aims to havetargets base salaries at or around the market median, with the majority of NEO compensation consisting of incentive compensation to advance the Committee's pay-for-performanceCommittee’s pay for performance philosophy. This methodology drives higher realized compensation when our financial performance is stronger and lower realized compensation when our financial performance is weaker. It provides the Committee with the flexibility to respond to changing business conditions, manage compensation in accordance with career progression, and adjust compensation to reflect differences in executive experience and performance.


Tetra Tech 2024 Proxy Statement 42

TABLE OF CONTENTS Fiscal 2017
Compensation Discussion and Analysis
FY 2023 Base Salary

In November 2016,2022, the Compensation Committee approved the base salary adjustments if any, shown in the following table for our NEOs, and the adjustments were not retroactive to the beginning of fiscal 2017.FY 2023. Accordingly, thesethe base salary amounts do not necessarily conform to the amounts contained in theSummary Compensation Table on page 61 of this proxy statement, which reflect the salary actually earned during fiscal 2017.FY 2023. Increases are generally driven by industryprior year performance, tenure, and peer benchmark data, subject to increase or decrease based on the NEO's performance and theoverall market median for positions with similar scope and responsibility.


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              The rationale for each increase was our fiscal 2016 performance, and the intent to position base salary around the market median.


FISCAL 2017FY 2023 NEO BASE SALARIES

Base Salaries
NameFY 2022 Base Salary ($)% IncreaseFY 2023 Base Salary ($)
Mr. Batrack1,175,0002.11,200,000
Mr. Burdick585,0006.8625,000
Dr. Shoemaker585,0000.0585,000
Mr. Hopson475,0007.4510,000
Mr. Argus475,0007.4510,000
  Name
 


Fiscal
2016 Base
Salary ($)



 %
Increase


 


Fiscal
2017 Base
Salary ($)



  Mr. Batrack    900,000   3.0    927,000  
  Mr. Burdick    462,000   3.0    476,000  
  Mr. Chu    472,000   3.0    486,000  
  Dr. Shoemaker    430,000   8.0    465,000  
  Ms. Salin    380,000   8.0    410,000  

Fiscal 2017FY 2023 AIP Award Program

The Compensation Committee grants AIP awards under our Executive Compensation Plan that was approved by our stockholders in 2014. No amounts are paid under the Executive Compensation Plan unless we have positive net income (as defined under the Executive Compensation Plan). The AIP awards are used to motivate NEOs to meet and exceed annual company objectives. These incentives are paid to reward the achievement of specified operating, financial, strategic, and individual measures and goals that are expected to contribute to stockholder value creation.

AIP Performance Measures and Targets

The AIP utilizesuses four financial metrics and one metric based on individual performance when the Committee is determining payments under the Executive Compensation Plan. Each November, a target level is established for each of the four financial metrics based on the annual operating plan (AOP)AOP for each of the RME and WEI business groups, as well as Tetra Techthe Company as a whole. In setting the targets, the Board and Compensation Committee aim to align our long-term financial goals and the drivers of our long-term stockholder value.

GRAPHIC



Tetra Tech 2024 Proxy Statement 43

Compensation Discussion and Analysis
The four financial metrics, including rationale for their inclusion in the AIP and the results of the fiscal 2017FY 2023 AIP, are illustrated in the table below:

below.
AIP Award Program Financial Metrics
Metric
FY17
Weighting


What it Measures and
How It Aligns


Threshold/
Maximum as a % of
Target



FY 2017
Target(1)
($ in
thousands)




FY 2017
Actual(2)
($ in
thousands)




FY 2016
Actual(3)
($ in
thousands)




FY 2023
Weighting
What it Measures and
How It Aligns
Threshold/
Maximum
as a % of
Target
FY 2023
Target
1
($ in
thousands)
FY 2023
Actual
2
($ in
thousands)
FY 2022
Actual
2
($ in
thousands)


Revenue

Gross Revenue



20%

20%




Measures the growth of our business and is a leading driver of stockholder value creation

creation.

Aligns with our growth and durable competitive advantage drivers





85% /
115%




Corporate:
$2,850,000

RME:
$1,597,075

WEI:
$1,100,098




Corporate:
$2,753,360

RME:
$1,659,952

WEI:
$1,146,366




Corporate:
$2,583,469

RME:
$1,569,702

WEI:
$1,028,281


​ ​ drivers.85% / 115%
Corporate:
$3,858,000
GSG:
$1,882,147
USG:
$497,036
Corporate:
$4,522,550
GSG:
$2,108,219
USG:
$514,480
Corporate:
$3,504,048
GSG:
$1,820,868
USG:
$443,485
Operating
Income
40%

​  


Operating Income




40%




Primary measure used by stockholders and analysts to evaluate our profitability

profitability.

Aligns with our margin, durable competitive advantage, and enterprise risk management drivers





75% /
125%




Corporate:
$187,885

RME:
$122,440

WEI:
$102,883




Corporate:
$176,419

RME:
$110,460

WEI:
$117,894




Corporate:
$158,226

RME:
$112,201

WEI:
$95,996


​ ​ ERM drivers.75% / 125%
Corporate:
$380,000
GSG:
$193,957
USG:
$53,335
Corporate:
$419,921
GSG:
$234.391
USG:
$65,766
Corporate:
$340,446
GSG:
$198,448
USG:
$49,576
Cash Flow20%

​  


Cash Flow




20%




Demonstrates our ability to collect on receivables billed to clients and allows us to invest in our business and return funds to stockholders through dividends and share repurchases

repurchases.

Aligns with our capital allocation driver





75% /
125%




Corporate:
$190,000

RME:
$122,000

WEI:
$105,000




Corporate:
$159,521

RME:
$71,551

WEI:
$118,003




Corporate:
$170,568

RME:
$119,010

WEI:
$97,648


​ ​ driver.75% / 125%
Corporate:
$353,000
GSG:
$163,000
USG:
$48,000
Corporate:
$405,421
GSG:
$287.552
USG:
$74,178
Corporate:
$336,188
GSG:
$157,265
USG:
$47,975
Backlog20%

​  


Backlog




20%




Positions us for growth going forward based upon authorized and funded projects

projects.

Aligns with our growth and durable competitive advantage drivers





85% /
115%




Corporate:
$2,650,000

RME:
$1,650,000

WEI:
$990,000




Corporate:
$2,541,105

RME:
$1,570,362

WEI:
$1,005,333




Corporate:
$2,378,894

RME:
$1,466,096

WEI:
$936,865


85% / 115%
Corporate:
$4,126,000
GSG:
$2,435,038
USG:
$621,080
Corporate:
$4,790,442
GSG:
$2,669,071
USG:
$694,682
Corporate:
$3,744,133
GSG:
$2,340,498
USG:
$661,747
(1)
1Corporate AOP is based on business group AOPs, augmented by planned acquisitions, whichthat are aligned with our business and stockholder interests. The AOPs for business groups include no acquisitions, since capital allocation strategy is implemented at Corporate.
(2)
2With respect to Corporate, results exclude the impact of purchase price accountingacquisition related charges, non-core disposition related charges, and aone-time, non-recurring tax settlementadjustments in fiscal 2017.FY 2023. With respect to RME,the business groups, results include only 50% of the impact of an acquisitionacquisitions in fiscal 2017.FY 2023. This inclusion reflects the business group president'spresidents’ responsibility to oversee the performance of and successfully integrate acquisitions.
(3)
With respect to Corporate, results exclude the impact of purchase price accounting, acquisition and integration expenses.

Table of Contents

              Each NEO'sThe AIP award isawards for our NEOs are based on the level of achievement of corporate (for Mr. Batrack, Mr. Burdick and Ms. Salin) orperformance of the business group (for Mr. Chu and Dr. Shoemaker)for which they were responsible. The chart below indicates respective weightings for business performance for each of these targets. NEO.

[MISSING IMAGE: tbl_awardbusiness-pn.jpg]

Tetra Tech 2024 Proxy Statement 44

Compensation Discussion and Analysis
Minimum (threshold), target, and maximum performance criteria and payouts were established for each metric as indicated above. The payout is 50% of target at threshold, 100% of target at target, and 200% of target at maximum,Payout percentages are reflected in the table below with a straight line interpolation from minimum tofor performance between threshold and target and frombetween target toand maximum. Accordingly, noNo bonus is earned with respect to a metric if performance is below threshold, and no additional bonus is earned for performance above maximum.

Payout Percentages
Performance LevelPayout
Less than Threshold0%
Threshold50%
Target100%
Maximum200%
Further, a financial modifier or "growth factor"“growth factor,” is applied to adjust the payout, either upward or downward, based on whether the AOP target is aggressive or conservative as compared to the prior year. This growth factor assists in validating the rigor of our AOP goals. Additional details on both the financial and individual performance elements of our AIP are provided below.

AIP Award Formula

NEO AIP awards are determined using the following formula:

GRAPHIC

*
IPF may modify Preliminary AIP Award by no more than 20%

Fiscal 2017formula.

[MISSING IMAGE: fc_aipaward-pn.jpg]
FY 2023 Target AIP Opportunities

The following table sets forth the target award and the maximum award possible as a percentage of fiscal 2017FY 2023 base salary for each NEO. No bonus is paid if performance is below the threshold performance goals.

Minimum, Target, and Maximum Percentages by NEO
NameMinimum Award
(%)
Target Award
(%)
Maximum Award
(%)
Mr. Batrack0150300
Mr. Burdick080160
Dr. Shoemaker080160
Mr. Hopson075150
Mr. Argus075150
Name 

Target Award
(%)
 



Maximum Award
as a % of Base
Salary (%)
 
 
Mr. Batrack  120  240 
Mr. Burdick  75  150 
Mr. Chu  75  150 
Dr. Shoemaker  75  150 
Ms. Salin  50  100 

These targets are derived in part from peer group and competitive survey analysis data and in part by the Compensation Committee'sCommittee’s judgment on the internal equity of the positions and scope of job responsibilities.

              CPF Range.

Corporate Performance Factor Range
The CPFCorporate Performance Factor (CPF) has a range of 0 to 2.0 with a target of 1.0 based on achievement of the AOP performance targets established in the AOP. Specifically, for each of the four metrics, the


Table of Contents

Compensation Committee reviewed fiscal 2017FY 2023 performance as a percentage of the target and determined an award percentage. The results were then averaged to determine the preliminary CPF.

CPF.

Growth Factor.Factor
The Compensation Committee believes in setting aggressive targets. Accordingly, the preliminary CPF was increased or decreased based upon the growth level of the AOP targets from the prior fiscal year. ThisThat approach rewards demanding targets and penalizes less strenuous targets.

Tetra Tech 2024 Proxy Statement 45

Compensation Discussion and Analysis
targets established with smaller increases relative to the prior year. The growth factors indicated below were applied to each metric and the results were averaged to determine the final CPF.

CPF.
Growth % of AOP Target from
Prior Fiscal Year Results
Growth % of AOP Target from
Prior Fiscal Year


Growth Factor Applied to

Preliminary CPF


Less than 5%0.9
Less than 5%0.9
Greater than 5% to, but less than 10%1.0
1.0
Greater than 10% to, but less than 15%1.1
1.1
Greater than 15%1.2
1.2

Fiscal 2017

FY 2023 CPF Modifiers

The following tables show the AIP financial modifiers for our NEOs for fiscal 2017.FY 2023. Our performance resulted in modifiers of0.956 1.744 for Mr. Batrack, Mr. Burdick, Dr. Shoemaker, and Ms. SalinMr. Hopson based on Corporate results0.734 and 1.705 for Mr. ChuArgus based on RMEGovernment Services Group (GSG) and US Government Division (USG) results, and1.409weighted 25% for Dr. Shoemaker based on WEIGSG results and 75% for USG results. The weighting of the gross revenue, operating income, cash flow, and backlog factors was 20%, 40%, 20%, and 20%, respectively.


CORPORATE PERFORMANCE

Corporate Performance
($ in thousands)

ObjectiveActual
FY 2022
Actual
FY 2023
Target
FY 2023
Actual
FY 2023
as a % of
Target
FY 2023
Preliminary
CPF
(0-2.0)
Growth % /
Growth
Factor
WeightFinal CPF
(0-2.0)
Revenue3,504,0484,522,5503,858,000117.232.00010/1.10.22.000
Operating Income340,446419,921380,000110.511.42012/1.10.41.562
Cash Flow336,188405,421353,000114.851.5945/1.00.21.594
Backlog3,744,1334,790,4424,126,000116.102.0010/1.10.22.000
CPF1.6871.744
Objective 

Actual
FY 2016(1)
 



Actual
FY 2017(2)
 



Target
FY 2017
 



Actual FY 2017
as a % of Target
FY 2017
 




Preliminary
CPF
(0-2.0)
 




Growth % /
Growth
Factor
 




Weight 

Final CPF
(0-2.0)
 
 
Gross Revenue  2,583,469  2,753,360  2,850,000  96.61  0.887  10/1.1  0.2  0.976 
Operating Income  158,226  176,419  187,885  93.90  0.878  19/1.2  0.4  1.054 
Cash Flow  170,568  159,521  190,000  83.96  0.679  11/1.1  0.2  0.747 
Backlog  2,378,894  2,541,105  2,650,000  95.89  0.863  11/1.1  0.2  0.949 
               0.837        0.956 

(1)
Reflects the impact of non-cash goodwill and contingent consideration liabilities.
(2)
Reflects the impact of non-cash goodwill and contingent consideration liabilities, and a tax settlement.


RME PERFORMANCE
GSG Performance
($ in thousands)

ObjectiveActual
FY 2022
Actual
FY 20231
Target
FY 2023
Actual
FY 2023
as a % of
Target
FY 2023
Preliminary
CPF
(0-2.0)
Growth % /
Growth
Factor
WeightFinal CPF
(0-2.0)
Revenue1,820,8682,108,2191,882,147112.011.8013/0.90.21.621
Operating Income198,448234,391193,957120.851.834-2/0.90.41.650
Cash Flow157,265287,552163,000176.412.0004/0.90.21.800
Backlog2,340,4982,669,0712,435,038109.611.6414/0.90.21.477
CPF1.8221.640
Objective 

Actual
FY 2016
 



Actual
FY 2017(1)
 



Target
FY 2017
 



Actual FY 2017
as a % of Target
FY 2017
 




Preliminary
CPF (0-2.0)
 



Growth % /
Growth
Factor
 




Weight 

Final CPF
(0-2.0)
 
 
Gross Revenue  1,569,702  1,659,952  1,597,075  103.94  1.262  2/0.9  0.2  1.136 
Operating Income  112,201  110,460  122,440  90.22  0.804  9/1.0  0.4  0.804 
Cash Flow  119,010  71,551  122,000  58.65    3/0.9  0.2   
Backlog  1,466,096  1,570,362  1,650,000  95.17  0.839  13/1.1  0.2  0.923 
               0.742        0.734 

(1)
1Reflects 50% of the impact of an acquisition.
acquisitions


Tetra Tech 2024 Proxy Statement 46

Compensation Discussion and Analysis
USG Performance
($ in thousands)

ObjectiveActual
FY 2022
Actual
FY 20231
Target
FY 2023
Actual
FY 2023
as a % of
Target
FY 2023
Preliminary
CPF
(0-2.0)
Growth % /
Growth
Factor
WeightFinal CPF
(0-2.0)
Revenue443,485514,480497,036103.511.23412/1.10.21.357
Operating Income49,57665,76653,335123.311.9328/10.41.932
Cash Flow47,97574,17848,000154.542.0000/0.90.21.800
Backlog661,747694,682621,080111.851.790-6/0.90.21.611
CPF1.7781.727
Objective 

Actual
FY 2016
 



Actual
FY 2017(1)
 



Target
FY 2017
 



Actual FY 2017
as a % of Target
FY 2017
 




Preliminary
CPF
(0-2.0)
 




Growth % /
Growth
Factor
 




Weight 

Final CPF
(0-2.0)
 
 
Gross Revenue  1,028,281  1,146,366  1,100,098  104.21  1.280  7/1.0  0.2  1.280 
Operating Income  95,996  117,894  102,883  114.59  1.584  7/1.0  0.4  1.584 
Cash Flow  97,648  118,003  105,000  112.38  1.495  8/1.0  0.2  1.495 
Backlog  936,865  1,005,333  990,000  101.55  1.103  6/1.0  0.2  1.103 
               1.409        1.409 
1 Reflects 50% of the impact of acquisitions.

Fiscal 2017

FY 2023 NEO Performance Evaluations and IPF Modifiers

The Compensation Committee may adjust each NEO's preliminary AIP awardNEO’s compensation under the Executive Compensation Plan by no more than 20% based upon the NEO's IPF. The IPF for each NEO other thanNEO’s individual performance. For adjustments to the CEO and the CFO is determined by the Compensation Committee following a recommendation by the CEO (for each NEO other than with respect to himself). The IPF for the CFO is determined jointly byCFO’s compensation based on individual performance, the Audit Committee and Compensation Committee following a recommendation by the CEO. The IPF for the CEO is determined by the Compensation Committee based on its review of the CEO's annual performance.

would jointly approve them.
IPF



Adjustment
Factor to
CPF (%)



Less than 0.80–20
0.80 - 0.90–10
0.91 - 1.090
1.10 - 1.19+10
Equal to or greater than 1.20+20

              Each IPF isAdjustments would be based on an assessment of the NEO'sNEO’s performance, including contributioncontributions to the successful achievement of annual operating goals, leadership in such NEO'sthe NEO’s area of responsibility, strategic planning, and implementation of applicable corporate objectives.

In fiscal 2017,FY 2023, the operational objectives were as follows:

maintaining
Advancing our culture of diversity, equity, and inclusion

Advancing our ESG programs

Maintaining high standards in business ethics;

ethics
maintaining
Maintaining high standards in customer service;

service
enhancing
Enhancing our organizational structure;

structure
developing
Providing a safe and healthy workplace for employees

Developing a three-year strategic plan that achieves value creation objectives;

objectives
further
Further implementing the contract management process to minimize risk and surprises, which aligns with our enterprise risk management driver;

ERM driver
improving
Improving key management metrics and reporting;

reporting
improving corporate-wide
Improving corporate wide marketing functions and processes;processes

Table of Contents

      winning
Winning key/targeted program competitions, which aligns with our growth driver;

driver
further
Further implementing our enterprise resource planning system migration plan;

plan
identifying
Identifying succession candidates for all executive positions;

positions
targeting
Targeting corporate general and administrative expenseexpenses not to not exceed a specified percentage of gross revenue;

revenue
reducing
Reducing legal and risk management insurance expenses while maintaining service levels; and

providing a safe and healthy workplace for employees.
levels

Table of Contents

              In determining the IPF and associated adjustment factor for our NEOs,

For FY 2023, the Compensation Committee notedconsidered the following highlightsindividual performance of each of the NEOs and approved a 20% upward modification to the AIP awards of Mr. Batrack, Mr. Burdick, and Mr. Hopson, and a 10% upward modification to the AIP awards of Dr. Shoemaker and Mr. Argus, all in recognition of their respectiveextraordinary contributions during an unprecedented fiscal 2017 performance:

year. For Mr. Burdick, the approval was provided jointly by the Compensation Committee and the Audit Committee. The basis for these modifications is described below.

Tetra Tech 2024 Proxy Statement 47

Compensation Discussion and Analysis
​  Name
Performance Highlights
Overall
Score/
IPF



Adjustment
to CPF


Mr. Batrack

Developed forward strategic plan tied to key drivers to build stockholder wealth

Successful growth initiatives, including International, Department of Justice, Water Infrastructure, and Department of Defense

Improved margin and increased high-end consulting to yield an improved market valuation

Good growth year-over-year in net revenue, operating income, EPS and backlog

Improved absolute TSR and relative TSR to peers

Improved safety metrics vs. industry national average

1.00None
Mr. Burdick

Negotiated favorable amendments to credit facility

Played a key role in an acquisition with favorable terms

Implemented bank services and credit facility for the Asia-Pacific region, which resulted in interest rate and bank fee savings

Identified potentially negative accounting adjustments and implemented changes, and identified future profit improvements

1.02None
Mr. Chu

Relocated to Australia to manage acquisition integration

Presided over inconsistent performance of RME operations in North America

0.91None
Dr. Shoemaker

Led the WEI group, which had strong financial performance and positioned the operations in key markets that will help differentiate Tetra Tech as a high-end consulting firm.

Played a key role in the Tetra Tech Leadership Academy, and was highly effective at identifying, developing, and promoting talented staff who have the potential to rise to senior leadership.

1.08None
Ms. Salin

Led the recently-completed acquisition of a sustainable infrastructure design company in the U.S.

Worked with international advisors to complete the purchase of an Australian-based consulting company

Completed all filings required by the SEC and other regulatory agencies

1.05None
Mr. Batrack continued to successfully implement our ongoing Strategic Plan, tied to key drivers to create stockholder value. As a result of his leadership and strategy execution, Tetra Tech achieved historic performance in FY 2023, reaching all-time record highs in revenue, net revenue, operating income, adjusted EBITDA, earnings and cashflow. In addition, Mr. Batrack personally oversaw the acquisition and integration of RPS Group, the largest transaction in Tetra Tech’s history with the addition of 5,000 employees. Notably, he facilitated the sustained growth of our high-margin, highly differentiated operations for both the legacy Tetra Tech business as well as the new RPS Group. In furtherance of our digital strategy, Mr. Batrack launched Tetra Tech’s software subscription practice. Following the implementation of flexible work arrangements, he initiated a comprehensive real estate consolidation program, resulting in significant annual savings. He also continued to develop, train, and retain a strong and qualified executive team with a focus on succession planning throughout the Company, resulting in the promotions of diverse and internal candidates to key operational leadership positions.

TableMr. Burdick contributed to Tetra Tech’s successful FY 2023 through strong financial management across the global operations. He was instrumental to the success of Contents

Fiscal 2017the RPS Group acquisition, contributing to every component of the transaction and integration process. Importantly, he oversaw the expansion of our sustainability-linked credit facility to fund the transaction, structured a foreign exchange hedge which generated a significant gain and reduced leverage, and managed the issuance of convertible notes to obtain advantageous rates to the benefit of Tetra Tech. In addition, Mr. Burdick facilitated achievement of sustainability goals in our credit facility, resulting in substantial interest savings to the Company.

Dr. Shoemaker led our sustainability and leadership development functions. As our chief sustainability officer, she executed on the plan to achieve our 2025 interim targets and 2030 sustainability goals outlined in our comprehensive sustainability report. Dr. Shoemaker personally spearheaded the integration of RPS Group’s Asia Pacific operations, ensuring continuity and collaboration among the combined businesses. She continued to oversee our Leadership Academy to effectively identify, develop, and promote a diverse group of employees with potential to rise to senior leadership roles. She also led our company-wide strategic hiring initiative and served as executive sponsor for our new software subscription practice.
Mr. Hopson advised our Board of Directors and executive leadership on corporate governance and social responsibility issues. He oversaw the resolution of significant litigation matters and supported finance initiatives, including the credit facility and convertible note offering. He played a key role in the RPS Group transaction and integration, and orchestrated the reorganization of the RPS Group legal and human resources functions globally. Mr. Hopson also supported the Board of Directors in its executive and director succession planning processes and coordinated new director onboarding. He continued to enhance our global ethics and compliance program and championed our DEI efforts as executive sponsor and was recognized by the Association of Corporate Counsel for these efforts. With responsibility for Tetra Tech’s Human Resources function, Mr. Hopson oversaw the implementation of a new employee performance management process and spearheaded initiatives that led to industry-leading low voluntary turnover rates.
Mr. Argus drove performance in the U.S. government focused operations, resulting in strong performance for GSG in FY 2023. He led his team to significant contributions to the overall increase in backlog and enhanced visibility for FY 2024. He also provided leadership on the identification, due diligence, acquisition, and integration of a federal IT business, adding significant value and market position within the data analytics/AI market for the Company. In addition, Mr. Argus expanded the Fearless Entrepreneur program he founded to train early career employees to foster the future growth and success of our operations, which resulted in over 150 new project wins in FY 2023.
FY 2023 AIP Awards

Our NEOs received the AIP awards shown in the following table for fiscal 2017,FY 2023, based on their respective base salary at fiscal 2017 year-end (FYE) 2023, AIP opportunity, financial modifier, and individual modifier:

performance modifier.
FY 2023 AIP Awards by NEO
NameFY 2023
Base Salary ($)
Target Award
Percentage (%)
Financial Modifier
(CPF)
Individual Performance
Modifier
AIP Award ($)
Mr. Batrack1,200,0001501.7441.2003,767,040
Mr. Burdick625,000801.7441.2001,046,400
Dr. Shoemaker585,000801.7441.100897,811
Mr. Hopson510,000751.7441.200800,496
Mr. Argus510,000751.7051.100717,484

Tetra Tech 2024 Proxy Statement 48

Compensation Discussion and Analysis
Name 

Fiscal 2017
Base Salary
($)
 




Target
Award
Percentage
(%)
 





Financial
Modifier
(CPF)
 




Individual
Modifier
(IPF %
Adjustment
to CPF)
 






AIP Award ($)  
Mr. Batrack  927,000  120  0.956  0  1,063,000 
Mr. Burdick  476,000  75  0.956  0  341,000 
Mr. Chu  486,000  75  0.734  0  267,000 
Dr. Shoemaker  465,000  75  1.409  0  491,000 
Ms. Salin  410,000  50  0.956  0  196,000 
FY 2023 SPECIAL ONE-TIME INCENTIVE PAYMENT

Fiscal 2017

In special cases, the Compensation Committee may determine to provide discretionary cash bonuses to our NEOs. In recognition of the substantial effort necessary to structure and complete the acquisition and integration of RPS Group, the Compensation Committee, in consultation with Meridian, approved a special one-time incentive payment to several senior executives, including many of the NEOs. The Compensation Committee determined this was appropriate for certain individuals based on the level of additional work required and the resulting success of the transaction, integration and financing efforts related to the RPS Group acquisition. The specific leadership accomplishments that influenced the Compensation Committee’s decisions are summarized above.
FY 2023 LTI Award Program

Our LTI program provides variable incentive compensation to enhance the alignment of executive interests with stockholder interests, with an emphasis on performance-based vesting. Accordingly, the LTI awards granted in fiscal 2017 wereFY 2023 comprised the following.
PSU and RSU Percentages of the following:

FY 2023 LTI Awards
Type of Award
Type of Award
% of LTI
(By Value)


Vesting
Rationale
(by value)VestingRationale
PSUs60%



PSUs




50%




Determined at conclusion of a three-year performance period, with vesting determined 50% by EPS growth and 50% by relative TSR




Performance-based; alignment with stockholder interests


​ ​  and subject to the holder’s continuous employment by Tetra Tech through the applicable vesting datePerformance-based; alignment with stockholder interests
RSUs40%



RSUs




25%




25% on each of the first through fourth anniversaries of the grant date,per year, subject to the holder'sholder’s continuous employment by usTetra Tech through the applicable vesting date




Retention; facilitate stock ownership; alignment with stockholder interests


​ ​ 



Stock Options




25%




25% on each of the first through fourth anniversaries of the grant date, subject to the holder's continuous employment by us through the applicable vesting date




Performance-based; long-term alignment with stockholder interests


​ ​ 

Fiscal 2017 LTI Awards

In fiscal 2017,FY 2023, the Compensation Committee granted the LTI awards shown in the following table. The target LTI value for each NEO was determined by the Compensation Committee and targeted atwithin a competitive range of the market median, based on a peer company analysis prepared by Meridian.while internal equity, retention, and individual performance and role—among other factors—were also considered. The number of PSUs stock options and RSUs awarded wereto each NEO was based on the closing price for shares of our common stock on November 16, 2016. 2022.
As a result of the required use of accounting methodology for determining grant date fair value in the Summary Compensation Table on page 61 of this proxy statement for PSUs with TSR vesting, certain total LTI values exceeded the corresponding target LTI values.


Table The amounts listed in the table include the grant date fair value of Contents


FISCAL 2017PSUs, without adjustment for forfeitures. The actual number of shares issued can range from 0% to 200% of the target shares at the time of grant.

The performance condition component of the fair value of PSUs was determined based on the fair market value of our common stock on the date of grant. The market condition component of the fair value of the PSUs was determined as of the date of grant using the Monte Carlo simulation method, which uses multiple input variables to estimate the probability of meeting the performance objectives established for the award, including the volatility of our stock price and other assumptions appropriate for determining fair value. The amounts also include the grant date fair value of RSUs, without adjustment for forfeitures, using the closing price per share of our common stock on the grant date.
FY 2023 NEO LTI AWARDS

Awards
NameTarget LTI Value
for FY 2023 ($)
PSUs (#)PSUs ($)RSUs (#)RSUs ($)
Grant Date Fair
Value ($)1
Mr. Batrack6,000,00022,8174,473,46215,2112,385,5416,859,003
Mr. Burdick1,000,0003,803745,5772,535398,5641,143,141
Dr. Shoemaker1,000,0003,803745,5772,535397,5641,143,141
Mr. Hopson800,0003,042596,4152,028318,051914,466
Mr. Argus800,0003,042596,4152,028318,051914,466
1 Accounting value as determined under Accounting Standards Codification (ASC) Topic 718.

Tetra Tech 2024 Proxy Statement 49

Compensation Discussion and Analysis

 

 

Name


 


Target LTI
Value for
FY 17



 
PSUs (#)
 
PSUs ($)
 


Stock
Options
(#)



 


Stock
Options
($)



 
RSUs (#)
 
RSUs ($)
 

Total LTI
Value ($)


 

 

Mr. Batrack

    3,150,000    37,815    1,828,725    62,599    773,098    18,908    771,446    3,373,269  

 

 

Mr. Burdick

    575,000    6,903    333,781    11,427    141,123    3,451    140,801    615,705  

 

 

Mr. Chu

    575,000    6,903    333,781    11,427    141,123    3,451    140,801    615,705  

 

 

Dr. Shoemaker

    575,000    6,903    333,781    11,427    141,123    3,451    140,801    615,705  

 

 

Ms. Salin

    380,000    4,562    220,619    7,552    93,267    2,281    93,065    406,951  

LTI awards are generally granted annually after the close of the fiscal year, shortly after we file our Form 10-K with the SEC.year. The Compensation Committee'sCommittee’s policy is to grant these equity awards following the public release of our fourth quarter and fiscal year financial results, during an open trading window, and to establish grant dates in advance.

Performance Share Units (PSUs);Stock Units: Three-Year Performance Period

The PSUs awarded to our NEOs cliff-vestcliff vest after a three-year performance period, subject to achievement of the applicable performance goals. Vesting is based 50% upon our EPS growth and 50% upon relative TSR performance. Since target LTI opportunity is set atwithin a competitive range of the market median, TSR performance at the 50th50th percentile of the TSR peer group and 100% TSR vesting would only result in payments atfrom TSR vesting within a competitive range of the market median. If TSR performance is less than the 50th50th percentile, the resulting payments would be appropriately below market median.

With respect to the determination of EPS growth, PSUs will vest as follows, based on Adjustedadjusted EPS as defined below, achieved during the performance period.

EPS growth will be measured by averaging EPS change on a point-to-point basis during the three-year performance period.
VestingAdjusted EPS Growth
0%less than 5%
60%5 to 9%
100%10 to 14%
120%15 to 19%
140%20 to 24%
160%25 to 29%
180%30 to 34%
200%equal to or greater than 35%

Our Adjustedadjusted EPS is the fully diluted earnings per shareEPS from our continuing operations, which is then adjusted to reflect the impacts from the following in order to ensure consistency during the vesting period:

goodwill
Goodwill impairment

accounting
Accounting changes requiring current and prior period adjustments due to materiality

changes
Changes in newly issued or existing accounting principles

the
The settlement of tax audits for more or less than amounts previously recorded

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      gains
Gains or losses from dispositions of subsidiaries and significant business lines and

costs
Impact of adjustments to earn out liabilities related to acquisitions

Costs incurred in connection with acquisitions, mergers, or debt restructurings.

restructurings

Our relative TSR performance is measured as our percentile-rankingpercentile ranking within theeach TSR peer group. Equal weight is given to the industry peer group and the S&P 1000. With respect to the determination of relative TSR performance, PSUs will vest as follows based on relative TSR performance achieved during the performance period.

VestingRelative TSR Performance
(Percentile)
0%less than 30%
20%30%
60%40%
100%50%
125%60%
150%70%
175%80%
200%equal to or greater than 90%

For determining our relative TSR for purposes of PSU vesting, the Compensation Committee uses a peer group that represents the industry in which we broadly compete for business and investor capital and have similar business profiles.capital. The TSR peer group is comprised of 17comprises the 16 U.S. public companies listed in the following table, satisfying objective criteria for industry classification and revenue size, the names of which are as follows:

size.
ABM Industries, Inc.MYR GroupMatrix, Inc.
Aegion CorporationMcDermott International, Inc.
Clean Harbors, Inc.MYR Group Inc.
Covanta Holding CorporationPrimoris Services Corporation
Covanta Holding CorporationDycom Industries Inc.Quanta Services, Inc.
Dycom Industries Inc.Stantec Inc.
EMCOR Group, Inc.Team,Stantec Inc.
KBR, Inc.Team, Inc.
MasTec, Inc.Waste Connections, Inc.
MasTec, Inc.Willbros Group, Inc.
Matrix, Inc.

Our TSR peer group is different than our compensation benchmarking peer group (listed under "Usein the Compensation Peer Group section on page 54 of Market Survey Data and Peer Group" below) because they support different company needs. For relative TSRthis proxy statement), as it includes companies that may be too large or too small for our benchmarking to determine LTI payout, our former compensation consultant provided an analysis of ourpeer group but are still viewed as competitors for investor capital, and noted that the revenue and/or market cap range could be broader than that used for compensation benchmarking purposes.

capital.

Restricted Stock Options

Units

All stock options are non-qualified andRSUs vest in equal annual installments over four years provided that the NEO remains employed by us through the applicable vesting date. Options granted in November 2016 expire on the tenth anniversary of the grant date, and the exercise price represents the closing price per share of our common stock on the grant date. The option grant places a significant portion of the NEOs' total compensation at risk, since the option grant delivers a return only if our common stock appreciates over the option's term. Further, the vesting provisions are designed to retain the services of the NEO for an extended duration.


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Restricted Stock Units (RSUs)

              All RSUs vest in equal annual installments over four years provided that the executive officer remains employed by usTetra Tech through the applicable vesting date. These vesting provisions are designed to retain the services of the NEO for an extended duration.


Tetra Tech 2024 Proxy Statement 50

Compensation Discussion and Analysis
Other Benefits
Nonqualified Deferred Compensation

Our NEOs are eligible to participate in our nonqualified deferred compensation plan,Deferred Compensation Plan (DCP), which allows eligible employees to defer up to 80% of their base salary, AIP award, and PSU/RSU awards. The plan provides NEOs, other eligible employees, and non-employeenonemployee directors with a long-term capital accumulation opportunity because savings accumulate on a pre-taxpretax basis. Participating executivesParticipants may select from among a number of investment options. The plan does not offer above-market interest rates. Deferrals are 100% vested. We do not make matching or any other contributions under the plan. Please referRefer to the table entitled"Nonqualified Deferred Compensation – Fiscal 2017"Compensation—FY 2023 table on page 65 in this proxy statement and the informationdetails set forth belowfollowing that table for additional information regarding the deferred compensation plan.

TERMINATION AND CHANGE IN CONTROL

DCP.

Termination and Change in Control
None of our NEOs has an employment agreement. The absence of employment agreementsagreement, which reflects our pay-for-performancepay for performance philosophy. IfSubject to the terms of the Tetra Tech, Inc. Change of Control Severance Plan (CIC Severance Plan) described in this section, if an NEO is no longer performing at the expected level, he or shethey can be terminated immediately without receiving a contractually-guaranteedcontractually guaranteed payment.

Our NEOs are eligible to participate in the CIC Severance Plan, which supersedes all prior change in control agreements we had with our NEOs.

Our NEOs are eligible for severance payments upon termination not for "cause"by us “without cause” or by the executive for "good“for good reason," in each case, within two yearsduring the two-year period following (or, in the case of a "changetermination without cause, 90-day period immediately preceding) a “change in control"control” of our companyCompany (each, a "qualifying termination"“qualifying termination”), in accordance with the terms and conditions of each NEO's respective change in control agreement.the CIC Severance Plan. In the event of such a qualifying termination, following a change in control, our NEOsthe NEO would be eligible to receivefor (1) the following lump sum cash severance pay equal to $4,078,800, subject to adjustmentpayments: (a) their current base salary plus target bonus for salary changes (inthe fiscal year of employment termination times a multiple (the multiple is 2.0 in the case of our CEO), 175%Mr. Batrack, 1.5 in the cases of base salary (inMr. Burdick and Dr. Shoemaker, and 1.0 in the casecases of Executive Vice Presidents) or 150% of base salary (in the case of Senior Vice Presidents)Messrs. Hopson and Argus); a pro-rata AIP award(b) their prorated target bonus for the fiscal year of termination, based on actual performance and the actual number of days the NEO worked during the year; theemployment termination; (c) any earned but unpaid bonus the NEO earned for the fiscal year immediately preceding the year of termination if such bonus had not yet been paid;their employment termination; and a payment(d) an amount equal to 102% of the cost of providing one year of healthmedical benefits (health, dental, and vision) to the NEO and his or herthe NEO’s dependents substantially similar to those provided immediately prior to such termination date.

              Underfor 24 months (in the current change in control agreements,case of Mr. Batrack), 18 months (in the cases of Mr. Burdick and Dr. Shoemaker), and 12 months (in the cases of Messrs. Hopson and Argus); and (2) full vesting of outstanding unvested stock options, restricted stock, and RSUs that vest solely based on continued employment, and vesting of equity awards granted to our CEO wouldthat vest only in the eventwhole or in part on achievement of a qualifying termination within two years after the change in control, with time-based equity awards vesting in full, and performance-based equity awards vestingperformance criteria based on actual performance results. For all other NEOs, allNo outstanding and unvested equity awards granted on or after November 3, 2014held by our NEOs would automatically vest only in the event of a qualifying termination within two years after the change in control, with time-based equity awards vesting in full, and performance-based equity awards vesting based on actual performance results, while all equity awards granted prior to November 3, 2014 would vest in full upon a change in control, regardlesscontrol.

In addition, if a participant’s employment is terminated because of whether any applicable performance targets have been met (as oftheir death or “disability” during the date of this proxy statement, all equity awards granted prior to November 3, 2014 have vested in accordance with their normal vesting schedule). Our NEOs are not eligible to receive any excise tax gross-up on amounts payable under thetwo years following a change in control, agreements or otherwise. However, if anthe NEO would otherwise incurreceive their prorated target bonus for the fiscal year of employment termination and any earned but unpaid bonus for the preceding fiscal year. All payments are contingent on the execution of a release and continued compliance with certain restrictive covenants set forth in the CIC Severance Plan.
The payments and benefits provided for under the CIC Severance Plan would be reduced to the extent that they would trigger excise taxes under Section 4999 of the Internal Revenue Code, (or be within $1,000 of doing so), the NEO's payments will be reduced so that no excise taxes would be due, unless the NEO would be better off by at least $50,000 on an after-tax basis after taking into account all taxes, (including the excise taxes


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under Section 4999 of the Code) and receiving the full amount of the payments and benefits, in whichbenefits. In this case, the NEO will receivepayment and benefits would not be reduced. In no event is the full amount of hisCompany obligated to provide any tax gross up or her payments and benefits.

              Please refersimilar payment to "Potentialthe NEO.

Refer to the Potential Payments Upon Termination or Change in Control"Control section on page 65 in this CD&Aproxy statement for additional information regarding change in control events and outstanding awards granted to the NEOs.

COMPENSATION-SETTING PROCESS AND TOOLS

Compensation Setting Process

and Tools

Process
Each November, following the conclusion of our fiscal year on or about September 30, the Compensation Committee meets to determine the compensation for each executive officer,NEO as follows: (1) the base salary is set for the succeeding fiscal year; (2) the variable AIP award is determined for the prior fiscal year and a new AIP award target is determined for the succeeding fiscal year; and (3) the LTI awards are granted for the succeeding fiscal year. Accordingly, in November 2016,2022, the Compensation Committee determined the base salaries for fiscal 2017,FY 2023, the AIP awards for fiscal 2016FY 2022 based on fiscal 2016FY 2022 performance, and the LTI and AIP targets for fiscal 2017.FY 2023. In November 2017,2023, the Compensation Committee determined the base salaries for fiscal 2018,FY 2024, the AIP awards for fiscal 2017FY 2023 based on fiscal 2017FY 2023 performance, and the LTI awardsand AIP targets for fiscal 2018.

FY 2024.


Tetra Tech 2024 Proxy Statement 51

Compensation Discussion and Analysis
Use of Market Survey Data and Peer Group

The Compensation Committee began its fiscal 2017FY 2023 process of deciding how to compensate our NEOs by considering the competitive market data provided by our independent compensation consultant, Meridian, and our human resources staff.

The Compensation Committee uses the market survey data as a reference point to target TDC at or around the median, also giving consideration toconsidering factors such factors as tenure, individual performance, the individual'sindividual’s responsibilities, market factors, and succession and retention considerations.

retention.

The Compensation Committee retains and does not delegate any of its exclusive power to determine all matters of executive compensation and benefits, although it seeks input and recommendations from the CEO and our human resources staff. Further, the Compensation Committee and the Audit Committee jointly determine the individual performance of the CFO. The Compensation Committee reports to the Board of Directors on the major items covered at each Compensation Committee meeting.

Compensation Peer Group.Group
The Compensation Committee worked with Meridian to develop a broad, size-appropriatesize appropriate peer group with comparable annual revenue and market capitalization. The peer group was finalized in November 2016 and was used for fiscal 2017 pay decisions. This peer group consists of the companies listed in the table below. Arcadis N.V. was excluded from the market

Aegion CorporationLeidos Holdings, Inc.
Booz Allen Hamilton, Inc.ManTech International
CACI International Inc.McDermott International, Inc.
Dycom Industries Inc.Parsons Corporation
FTI Consulting, Inc.Science Applications Intl. Corp
ICF International, Inc.Stantec Inc.
KBR, Inc.WSP Global Inc.

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compensation statistics by Meridian due to insufficient available information regarding its executive compensation design.

Independent Oversight and Expertise
Company 

Fiscal 2016
Revenue
($ in Millions)
 




Trailing
12 Months
Revenue
($ in Millions)
 





Market Cap
on 8/31/17
($ in Millions)
 
 
The Advisory Board Company  803  799  2,168 
Aegion Corporation  1,222  1,310  684 
Arcadis N.V.  3,514  3,764  1,874 
Booz Allen Hamilton, Inc.  5,406  5,875  5,071 
CACI International Inc.  3,744  4,355  3,175 
CH2M Hill, Inc.  5,236  5,183  N/A 
Dycom Industries Inc.  2,673  3,067  2,507 
FTI Consulting, Inc.  1,810  1,771  1,309 
ICF International, Inc.  1,185  1,119  900 
KBR, Inc.  4,268  4,463  2,276 
Leidos Holdings, Inc.  7,043  9,594  8,819 
McDermott International, Inc.  2,636  2,508  1,744 
Navigant Consulting, Inc.  939  948  716 
Science Applications Intl. Corp  4,315  4,321  3,227 
Stantec Inc.  2,307  2,660  3,151 
WSP Global Inc.  4,749  5,157  4,244 

Median*

 

 

2,673

 

 

3,067

 

 

2,392

 

Tetra Tech

 

 

2,583

 

 

2,747

 

 

2,409

 

*
Excludes Arcadis N.V.

INDEPENDENT OVERSIGHT AND EXPERTISE

Our Board believes that hiring and retaining effective executives and providing them with market-competitivemarket competitive compensation are essential to the success of our companyCompany and advance the interests of our stockholders. The Compensation Committee, which is comprised solely of independent directors, has responsibilityis responsible for overseeing our executive compensation program.

Under its charter, the Compensation Committee has the authority, in its sole discretion and at our expense, to obtain advice and assistance from external advisors. The Committee may select, retain and terminate any compensation consultant or other external advisor and has sole authority to approve any such advisor'sadvisor’s fees and other terms and conditions of the retention. In retaining its advisors, the Committee must consider each advisor'sadvisor’s independence from management.

ADVISOR INDEPENDENCE

Advisor Independence
Meridian did not performprovide services for our companyCompany in fiscal 2017FY 2023 other than the work undertaken for or at the request of the Compensation Committee.

Meridian and the Compensation Committee have the following protocols in place to ensure their independence from management:

the
The Compensation Committee has the sole authority to select, retain, and terminate Meridian, as well as to authorize Meridian'sMeridian’s fees and determine the other terms and conditions that govern the engagement;engagement

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      the
The Compensation Committee directs Meridian onin the process for deliveryof delivering and communication ofcommunicating its work product, including its analyses, findings, conclusions, and recommendations;

recommendations
in
In the performance of its duties, Meridian is accountable and reports directly to the Committee; and

Compensation Committee
the
The Compensation Committee may consult with Meridian at any time, with or without members of management present, at the Committee'sCompensation Committee’s sole discretion.

discretion


Tetra Tech 2024 Proxy Statement 52

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Compensation Discussion and Analysis
In accordance with regulatory requirements, the Compensation Committee evaluated the following six factors to assess independence and conflicts of interest before it engaged Meridian to perform work in fiscal 2017:

      FY 2023:
the
The provision of other services to us by Meridian;

Meridian
the
The amount of fees received by Meridian from us, by Meridian, as a percentage of Meridian'sMeridian’s total revenues;

revenues
the
Meridian’s policies and procedures of Meridian that are designed to prevent conflicts of interest;

interest
any
Any business or personal relationship ofbetween a member of the Compensation Committee withand the regular members of Meridian'sMeridian’s executive compensation team thatwho serve us;

us
any
Any of our stock owned by the regular members of Meridian'sMeridian’s executive compensation team thatwho serve us; and

us
any
Any business or personal relationships between our executive officers and the regular members of Meridian'sMeridian’s executive compensation team thatwho serve us.

us

The Compensation Committee also obtained a representation letter from Meridian addressing these six factors and certain other matters related to its independence. Based on the Compensation Committee'sCommittee’s evaluation of these factors and the representations from each firm,Meridian, the Compensation Committee concluded that Meridian is an independent adviser and has no conflicts of interest with us.

STOCK OWNERSHIP GUIDELINES

Stock Ownership Guidelines
To further the goal of aligning the interests of executive officers and non-employeenonemployee directors with those of stockholders, we maintain a policy regarding minimum ownership of our shares. These ownership guidelines currently call for the following:

the
The CEO to own shares having a value equal to the lesser of at least six times the CEO'sCEO’s base salary or 170,000 shares;

each Executive Vice
The President to own shares having a value equal to the lesser of at least three times base salary or 40,000 shares;

each Senior Vice President
Each EVP to own shares having a value equal to the lesser ofat least three times base salary

Each SVP to own shares having a value equal to at least two times the executive officer'sofficer’s base salary or 20,000 shares; and

each non-employee
Each nonemployee director to own shares having a value equal to the lesser of at least threefive times the non-employee director'snonemployee director’s annual base cash retainer or 6,100 shares.

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Until an executive officer'sofficer’s or non-employee director'snonemployee director’s stock ownership requirement is met, the executive officer or non-employeenonemployee director must retain at least 75% of "gain shares"gain shares resulting from the exercise of a stock option or vesting of a performance share, PSU award, or RSU award. With respect to stock options, "gain shares"“gain shares” means the total number of shares of common stock that are being exercised less the number of shares, if any, used in the case of a cashless exercise to pay for the exercise price. With respect to performance share, PSU awards and RSU awards, "gain shares" meansgain shares are the total number of shares of common stock subject to any such equity award that vests. Gain shares do not include shares of common stock that are used to satisfy tax withholding obligations.

Each executive officer and non-employeenonemployee director has five years to attain the required ownership level. In addition to shares of common stock, vested but unexercised stock options, and vested and unvested performance shares, PSUs and RSUs count in determining stock ownership for purposes of the stock ownership guidelines. An executive officer or non-employeenonemployee director who fails to comply with the stock ownership guidelines will be required to use one-thirdone third of any net annual cash bonus or net annual retainer, as applicable, to purchase shares of our stock.

As of FYE 2023, all our directors and executive officers have met our stock ownership guidelines, taking into account the endphase-in requirements of fiscal 2017, allthe policy if applicable to such person, helping ensure the alignment of their interests with those of our executive officersstockholders.
Clawback Policy
We have adopted a Dodd-Frank Wall Street Reform and non-employee directors, other than Ms. Maguire who joinedConsumer Protection Act-compliant compensation recoupment policy in accordance with SEC and listing exchange requirements. In the Board in November 2016, met the stock ownership guidelines.

CLAWBACK POLICY

              If our company isevent we are required to prepare an accounting restatement, due to its material noncompliance withwe will recover any compensation received after the effective date by any current or former executive officer that is based wholly or in part upon the attainment of a financial reporting requirements under the securities laws, then each executive officer must return to us, or forfeit if not yet paid, a specified amount. The amount is any AIP payment received with respect to an award under our Executive Compensation Plan during the three-year period preceding the date on which our company is required to prepare the accounting restatement, based on the erroneous data less what would have been paidmeasure.

Insider Trading, Anti Hedging, and Anti Pledging Policy
In addition to the executive officer undergeneral provisions of our Insider Trading Policy, which prohibits all employees and directors from trading in our securities while in possession of material nonpublic information, the accounting restatementpolicy also strictly prohibits our employees and directors from

Tetra Tech 2024 Proxy Statement 53

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Compensation Discussion and Analysis
engaging in transactions in our securities involving puts, calls, or other derivative securities on an exchange or in any other organized market, selling our securities “short,” or entering into hedging or similar arrangements (e.g., exchange funds) involving our securities. The policy also prohibits our employees and directors from pledging our securities as determined by thecollateral for a loan or holding our securities in a margin account.
Tax Implications of Executive Compensation Committee.

TAX IMPLICATIONS OF EXECUTIVE COMPENSATION

The Compensation Committee considers the tax consequences to Tetra Techthe Company and itsour NEOs as one factor among many when structuring executive compensation.

Pay versus Performance Disclosure
Section 162(m)953(a) of the Internal Revenue Code

              Section 162(m)Dodd-Frank Wall Street Reform and Consumer Protection Act, and Item 402(v) of Regulation S-K, under the Securities Act prescribes the disclosure included in this section and does not necessarily align with how the Company views the link between the Company’s performance and NEO pay. Compensation actually paid (CAP), as determined under SEC requirements, does not reflect the actual amount of compensation earned by or paid to our NEOs during a covered fiscal year. Instead, CAP has been calculated in accordance with the new SEC rules, which include measurement of the Internal Revenue Code limitschanges in the amount we can annually deduct fromfair value of equity awards. CAP is a supplemental measure to be viewed alongside, not in replacement of, performance measures, and for further information concerning the Company’s pay-for-performance philosophy and how the Company aligns executive compensation with the Company’s performance, please refer to the Compensation Discussion and Analysis.

Pay versus Performance Table
Value of Initial Fixed $100
Invested Based On:
Year1
SCT Total
Compensation
for CEO
Compensation
Actually
Paid to CEO2
Average
SCT Total
Compensation
for Other
NEOs
Average
Compensation
Actually Paid to
Other NEOs3
Company
TSR
Peer
Group4
Net
Income
($M)
Revenue
($M)5
2023$11,885,517$16,020,470$2,595,666$3,337,863$169.64$173.28$273.4$4,522.6
2022$10,331,897$9,306,681$2,318,379$2,065,988$142.49$140.27$263.1$3,504.0
2021$7,908,335$18,481,077$2,109,249$3,740,891$167.37$124.91$232.8$3,212.5
Notes:
1 The CEO and other NEOs for the indicated years were as follows: (i) for 2023, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Hopson, and Argus, (ii) for 2022, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Amidon, and Hopson, (iii) and for 2021, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Argus, and Hopson.
2 Amounts reported in this column are based on total compensation reported for our CEO in the Summary Compensation Table for the indicated fiscal years and adjusted as shown in the tables below. Fair value of equity awards was computed in accordance with the Company’s methodology used for financial reporting purposes.
Fiscal YearSummary Compensation
Table Total
Adjustment to Summary
Compensation Table Totala
Compensation
Actually Paid
2023$11,885,517$4,134,952$16,020,470
2022$10,331,897($1,025,216)$9,306,681
2021$7,908,335$10,572,742$18,481,077
a See table below for calculation of Adjustment to Summary Compensation Table Total
Fiscal
Year
Deduction of Grant
Date Fair Value of
Current Year Equity
Awards
Addition of Fair
Value of Current
Year Equity Awards
at FYE
Additions (Deductions)
for Change in Value of
Prior Years’ Awards
Unvested at FYE
Additions (Deductions)
for Change in Value of
Prior Years’ Awards That
Vested in Fiscal Year
Dollar Value of Dividends
not Otherwise Reflected
in the Fair Value for
Covered Fiscal Year
Adjustment to
Summary
Compensation
Table Total
2023($6,859,003)$6,239,770$2,833,515$1,853,143$67,527$4,134,952
2022($6,281,608)$3,979,305($1,831,074)$3,024,666$83,495($1,025,216)
2021($4,601,813)$5,668,783$6,914,928$2,516,496$74,348$10,572,742
3 Amounts reported in this column are based on the average of the total compensation reported for our other NEOs in the Summary Compensation Table for the indicated fiscal years and adjusted as shown in the tables below. Fair value of equity awards was computed in accordance with the Company’s methodology used for financial reporting purposes.

Tetra Tech 2024 Proxy Statement 54

TABLE OF CONTENTS
Compensation Discussion and Analysis
Fiscal YearAverage Summary
Compensation Table
Total
Adjustment to Average
Summary Compensation
Table Totalb
Average
Compensation
Actually Paid
2023$2,595,666$742,198$3,337,863
2022$2,318,379($252,392)$2,065,988
2021$2,109,249$1,631,643$3,740,891
b See table below for calculation of Adjustment to Average Summary Compensation Table Total
Fiscal YearDeduction of
Grant Date Fair
Value of Current
Year Equity
Addition of Fair
Value of Current
Year Equity
Awards at FYE
Additions
(Deductions) for
Change in Value of
Prior Years’ Awards
Unvested at FYE
Additions
(Deductions) for
Change in Value of
Prior Years’ Awards
That Vested in
Fiscal Year
Dollar Value of
Dividends not
Otherwise Reflected
in the Fair Value for
Covered Fiscal Year
Adjustment to
Summary
Compensation
Table Total
2023($1,028,804)$935,927$520,160$303,504$11,411$742,198
2022($1,024,644)$649,101($335,039)$441,571$16,620($252,392)
2021($934,781)$1,151,515$1,068,729$333,464$12,715$1,631,643
4 For each indicated covered year, the peer group was composed of the following companies:
FY 2021: Booz Allen Hamilton Holding Co., CACI International, Dycom Industries, FTI Consulting, ICF International, KBR Inc., Leidos Holdings, ManTech International Corp., Parsons Corp., Science Applications International, Stantec Inc., and WSP Global
FY 2022: Booz Allen Hamilton Holding Co., CACI International, Dycom Industries, FTI Consulting, ICF International, KBR Inc., Leidos Holdings, Parsons Corp., Science Applications International, Stantec Inc., and WSP Global
FY 2023: Booz Allen Hamilton Holding Co., CACI International, Dycom Industries, FTI Consulting, ICF International, KBR Inc., Leidos Holdings, Parsons Corp., Science Applications International, Stantec Inc., and WSP Global
5 In accordance with SEC rules, the Company is required to include in the Pay versus Performance table the “most important” financial performance measure (as determined by the Company) used to link compensation actually paid to certainour named executive officers to $1 million unless, with respectCompany performance for the most recently completed fiscal year. The Company determined revenue, which is a metric included in our incentive program, meets this requirement and therefore, we have included this performance measure in the Pay versus Performance table.
Description of the Relationship Between Compensation Actually Paid to taxable years beginning before December 31, 2017 (including fiscal 2017our Named Executive Officers and fiscal 2018),Company Performance
The charts below describe the relationship between compensation actually paid (CAP) to our chief executive officer and the average of the compensation qualifies as "performance-based" under tax rules. The Tax Cuts and Job Act, which was signed into law on December 22, 2017, eliminates this exemption for "performance-based" compensation under Section 162(m) with respect to taxable years beginning after December 31, 2017. Accordingly, beginning with fiscal 2019, we will no longer be able to structure executive compensationactually paid to certainour other named executive officers in excess of $1 million to qualify(as calculated above) and our financial and stock performance for the indicated years. In addition, the first chart below compares our cumulative total shareholder return (TSR) and peer group cumulative TSR for the indicated years.
[MISSING IMAGE: bc_peergrouptsr-4c.jpg]

Tetra Tech 2024 Proxy Statement 55

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Compensation Discussion and Analysis
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Company’s Most Important Financial Performance Measures
The following were the most important financial performance measures (and non-financial performance measures), as "performance-based" under Section 162(m) in order to preservedetermined by the deductibility ofCompany, that link compensation (unless the compensation is provided pursuant to a written binding contract which was in effect on November 2, 2017, and which was not modified in any material respect on or after November 2, 2017). Rather, beginning with fiscal 2019, compensationactually paid to certain executive officers in excessour NEOs to the Company’s performance for the most recently completed fiscal year.

Revenue

Operating Income

Earnings per Share

Cash Provided by Operations

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Compensation Discussion and Analysis
All of $1 million will generally not be deductible. We believe that deductibility of executive compensation is an important consideration in structuring executive compensation, but we reserve the right to pay compensation and/or approve executive compensation arrangements that are not fully tax deductible if we believe that doing so is ininformation provided above under the best interests of our


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company and stockholders. For example, our time-based RSU awards with respect to fiscal 2017 are not intended to qualify as "performance-based" compensation under Section 162(m). In addition, even if it is intended that compensation be "performance-based", there is no guarantee that the deductions we claim under Section 162(m)“Pay Versus Performance Disclosure” heading will not be challenged or disallowed by the IRS.

              The AIP awards with respect to fiscal 2017 under our Executive Compensation Plan, which was last approved by our stockholders in 2014, are intendeddeemed to be "performance-based" compensationincorporated by reference into any filing of the Company under Section 162(m). The Executive Compensation Plan provides that our NEOs may receive a specified percentagethe Securities Act of our net income,1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date hereof and irrespective of any general incorporation language in each case as reported on our consolidated statements of operations forany such filing, except to the applicable fiscal year, as a maximum amount. The extent the Company specifically incorporates such information by reference.


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Compensation Committee may exercise its discretion to pay an amount substantially less than the maximum amount based on the performance factors that are discussed in the CD&A under the headingFiscal 2017 AIP Award Program – AIP Performance Measures and Targets. In addition to the AIP awards under the Executive Compensation Plan, our PSU awards with respect to fiscal 2017 are also intended to qualify as "performance-based" compensation under Section 162(m).


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Report
COMPENSATION COMMITTEE REPORT
Compensation Committee Report

The Compensation Committee of the Board of Directors has reviewed and discussed the Compensation Discussion and Analysis (CD&A)CD&A required by Item 402(b) of Regulation S-K with management and, based on its review and these discussions, has recommended to the Board of Directors that the CD&A be included or incorporated by reference ininto our fiscal year 2017FY 2023 Annual Report on Form 10-K and 20182024 proxy statement.

The Compensation Committee welcomes feedback regarding our executive compensation program. Stockholders may communicate with the individual members of the Committee by writing to the Compensation Committee Chair, c/o Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107.

Respectfully submitted by:
J. Kenneth Thompson, Chair
Patrick C. Haden
J. Christopher Lewis

Joanne M. Maguire
Christiana Obiaya
Kirsten M. Volpi

This Compensation Committee Report does not constitute soliciting material and should not be deemed filed or incorporated by reference into any of our filings under the Securities Act of 1933, as amended, or the Securities Exchange Act, of 1934, as amended, whether made before or after the date hereof, unless specifically incorporated by reference therein.

COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION

Compensation Committee Interlocks and Insider Participation
No member of the Compensation Committee was at any time during fiscal year 2017FY 2023 one of our officers or employees, and no member of the Compensation Committee had any relationship with us requiring disclosure under Item 404 of Regulation S-K. During fiscal year 2017,FY 2023, none of our executive officers has served on the board of directors or compensation committee of any other company, which company has or had one or more executive officers who served as a member of our Board of Directors or Compensation Committee.


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EXECUTIVE COMPENSATION TABLES

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TABLE OF CONTENTS SUMMARY COMPENSATION TABLE

Executive Compensation Tables
Executive Compensation Tables
Summary Compensation Table
The following table shows the compensation earned by or awarded to our NEOs during fiscal years 2017, 2016FYs 2023, 2022, and 20152021, in accordance with SEC regulations. Compensation as shown in the table does not necessarily reflect the compensation actually realized by our NEOs for thesethose years. For example, the amounts for 2023 set forth under "Stock Awards" in 2017the Stock Awards column relating to PSUs do not represent the actual amounts realized by our NEOs; rather they represent the aggregate grant date fair value for financial reporting purposes of those PSUs, which cliff vest subject to achievement of the applicable performance goals (based on 50% by EPS growth and 50% by relative TSR) at the end of a three-yearthree year performance period and ultimately may result in no such compensation being realized by the NEO.

Summary of Executive Compensation by NEO
Name and Principal PositionYear
Salary
($)1
Bonus2
Stock
Awards
($)3
Non-Equity
Incentive Plan 
Compensation
($)4
All Other
Compensation
($)5
Total
($)
Dan L. Batrack
Chairman, CEO
20231,196,1546,859,0033,767,04063,32111,885,517
20221,204,3276,281,6082,783,54962,41310,331,897
20211,090,3854,601,8132,154,90061,2377,908,335
Steven M. Burdick
EVP, CFO
2023618,846200,0001,143,1411,046,40050,0463,058,433
2022603,2691,128,581791,91545,3182,569,083
2021562,1151,035,393708,60144,7002,350,808
Leslie L. Shoemaker
EVP, Chief Sustainability and Leadership Development Officer
2023585,000100,0001,143,141897,81141,7882,767,740
2022603,2691,128,581791,91541,3492,565,114
2021562,1151,035,393708,60144,7002,350,808
Preston Hopson
SVP, General Counsel, and Secretary
2023504,615100,000914,466800,49646,3712,365,948
2022484,808920,707602,82045,0952,053,429
2021428,269862,941511,46344,8601,847,533
Roger R. Argus
SVP and President, GSG
2023504,615914,466717,48453,9762,190,541
2022484,808920,707541,47447,6511,994,640
2021428,269805,395606,58547,5961,887,845
Name and Principal
Position
 Year Salary(1) Bonus Non-Equity
Incentive
Plan
Compensation(2)
 Stock
Awards(3)
 Option
Awards(4)
 All Other
Compensation(5)
 Total 

Dan L. Batrack

  2017  922,327    1,063,000  2,600,171  773,098  37,777  5,396,373 

Chairman and Chief

  2016  900,000    1,368,000  2,642,162  794,406  36,733  5,741,301 

Executive Officer

  2015  900,000    1,048,680  2,641,055  787,503  41,956  5,419,194 

Steven M. Burdick

  
2017
  
473,577
  

  
341,000
  
474,582
  
141,123
  
40,245
  
1,470,527
 

Executive Vice President

  2016  459,923    440,000  471,812  141,857  40,363  1,553,955 

and Chief Financial Officer

  2015  446,154    330,000  445,997  134,376  40,414  1,396,941 

Ronald J. Chu(6)

  
2017
  
483,577
  

  
267,000
  
474,582
  
141,123
  
124,695
  
1,490,977
 

Executive Vice President

  2016  469,923    525,000  482,299  144,871  113,381  1,735,474 

and President of RME

  2015  454,231    340,000  445,997  134,376  38,928  1,413,532 

Leslie L. Shoemaker. 

  
2017
  
458,942
  

  
491,000
  
474,582
  
141,123
  
29,769
  
1,595,416
 

Executive Vice President

  2016  424,808    320,000  419,368  125,968  29,819  1,319,963 

and President of WEI

  2015  368,414    275,000  269,677  81,252  30,849  1,025,192 

Janis B. Salin. 

  
2017
  
382,731
  

  
196,000
  
313,684
  
93,267
  
42,116
  
1,027,798
 

Senior Vice President,

  2016  378,269    240,000  310,348  93,213  37,685  1,059,515 

General Counsel and Secretary

  2015  363,654    180,000  279,606  84,249  38,568  946,077 

(1)
1Amounts include any portions of salary deferred under our deferred compensation plan.DCP. Increases in base salary, if any, became effective in November of each year and were not retroactive to the beginning of the fiscal year. Accordingly, for a portion of a fiscal year, an NEO who received a base salary increasedincrease received base salary at the prior fiscal year'syear’s base salary rate. Effective November 17, 2017,
2 The amounts reported in the annual base salaries forBonus column represent the special one-time incentive payment awarded to certain NEOs for fiscal 2018 are as follows: Mr. Batrack, $940,000; Mr. Burdick, $490,000;FY 2023. The FY 2023 Special One-Time Incentive Payment section of the Compensation Discussion and Dr. Shoemaker, $490,000; Mr. Chu retired effective November 6, 2017, and Ms. Salin retired effective January 22, 2018.
(2)
The amounts listed in this column for fiscal 2017 reflectAnalysis, which begins on page 37, describes how the discretionary cash bonus awards paid to the relevant NEOs for fiscal 2017 performance, as further described in theCompensation Discussion & Analysis section of this proxy statement and the "Grants of Plan-Based Awards – Fiscal 2017" table below. The amounts listed in this column for fiscal 2016 and 2015 reflect the cash awards paid to the NEOs for performance in those fiscal years.
(3)
were determined.
3The amounts in this column reflect the aggregate grant date fair value of stock awards granted during the applicable fiscal year, without adjustment for forfeitures, and do not reflect compensation actually realized by our NEOs. For values actually realized by our NEOs during fiscal 2017,FY 2023, see the "ValueValue Realized on Vesting"Vesting column of the "OptionsOptions Exercised and Stock Vested – Fiscal 2017"Vested—FY 2023 table below.on page 64 of this proxy statement. Amounts in 20172023 include the grant date fair value of PSUs, without adjustment for forfeitures, which are payable at the end of a three-year performance period provided that the performance objectives are achieved as of the end of the period. The actual number of shares issued can range from 0% to 200% of the target shares at the time of grant. The performance objectives that determine the number of shares that may be earned for the PSUs are (i)(a) as to 50% of the award, growth in earnings per share,EPS, which is a performance condition under FASB ASC Topic 718, and (ii)(b) as to 50% of the award, TSR, which is a market condition under FASB ASC Topic 718, relative to the TSR of (A) 17(i) 16 companies objectively determined based on GICS code and revenue size (25% of award) and (B)(ii) the S&P 1000 (25% of award), in each case computed over the three-year performance period. The performance condition component of the fair value of PSUs was determined based on the

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fair market value of our common stock on the date of grant. The market condition component of the fair value of the PSUs was determined as of the date of grant using the Monte-CarloMonte Carlo simulation method, which utilizesuses multiple input variables to estimate the probability of meeting the performance objectives established for the award, including the volatility of our stock price and other assumptions appropriate for determining fair value. Based on thesethose computations, the grant date fair value of the PSU awards granted on November 18, 201616, 2022, to each NEO on that date were $40.80$156.83 per share for the performance condition component and $55.92$235.29 per share for the market condition component. The maximum grant date fair valuevalues of the PSUs granted in fiscal 2017FY 2023 (200% vesting) was $3,657,450, $667,562, $667,562, $667,562,were $8,946,924, $1,491,154, $1,491,154, $1,192,829, and $441,238$1,192,829 for Mr. Batrack, Mr. Burdick, Mr. Chu, Dr. Shoemaker, Mr. Hopson, and Ms. Salin,Mr. Argus, respectively.
(4)
The amounts Amounts in this column represent2023 also include the aggregate grant date fair values,value of RSUs, computed in accordance with FASB ASC Topic 718 and without adjustment for forfeitures, using the closing price per share of our common stock options granted duringon the applicable fiscal year. The grant date fair value of($156.83 per share).
4 The amounts listed in this column for FY 2023 reflect the stock optioncash awards granted on November 18, 2016 was $12.35 per share. For information on the valuation assumptions relating to stock option grants, referpaid to the note on Stockholders' Equity and Stock Compensation PlansNEOs for FY 2023 performance, as further described in the notesCompensation Discussion and Analysis section on page 37 of this proxy statement and the Grants of Plan Based Awards—FY 2023 table below. The amounts listed in this column for FYs 2022 and 2021 reflect the cash awards paid to consolidated financial statements containedthe NEOs for performance in our Annual Report on Form 10-K for thethose fiscal yearyears.

Tetra Tech 2024 Proxy Statement 59

Executive Compensation Tables
5 Figures in which the stock option was granted. There can be no assurance that these grant date fair values will ever be realized by the NEOs. See the "Grants of Plan-Based Awards – Fiscal 2017" table below for information on stock option grants made in fiscal 2017.
(5)
Consiststhis column consist of the employer contribution made on behalf of each of the NEOs to our health and welfare benefits and our qualified retirement plan, as well as the reimbursements for vehicle use, financing planning,financial and tax planning, memberships, and annual physical examinations describedexaminations. Amounts for Mr. Batrack are enumerated in the table below:
Company Contribution
to 401(k) Plan
Company Contribution
to Health and
Welfare Benefits
Automobile
Allowance
MembershipsFinancial and
Tax Planning
$17,602$14,589$10,800$16,330$4,000

Tetra Tech 2024 Proxy Statement 60

Executive Compensation Discussion & Analysis sectionTables
Grants of this proxy statement.
(6)
In January 2016, Mr. Chu relocated to Sydney, Australia at our request to serve as Chief Executive Officer of Coffey. The All Other Compensation amount for Mr. Chu reflects benefits of USD $88,533 related to this international assignment, including (i) housing benefits of $72,321, (ii) vehicle benefits of $5,879 and (iii) other miscellaneous benefits of $10,333. These expatriate benefits ceased upon his repatriation in October 2017.
Plan Based Awards–FY 2023

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GRANTS OF PLAN-BASED AWARDS – FISCAL 2017

The following table provides information regarding grants of plan-based incentive awards made to our NEOs during fiscal 2017.

FY 2023.
Estimated Possible Payouts under
Non-Equity Incentive Plan Awards
Estimated Possible Payouts under
Equity Incentive Plan Awards
All Other
Stock
Awards:
Shares of
Stock or
Units (#)
All Other
Option
Awards:
Securities
Underlying
Options (#)
Exercise
or Base
Price of
Option
Awards ($)
Grant
Date Fair
Value of
Stock and
Option
Awards ($)
NameGrant DateThreshold
($)
Target
($)
Maximum
($)
Threshold
(#)
Target
(#)
Maximum
(#)
Mr. Batrack
1
01,645,0003,290,000
11/16/222
022,81745,6344,473,462
11/16/223
15,2112,385,541
Total6,859,003
Mr. Burdick
1
0468,000936,000
11/16/222
03,8037,606745,577
11/16/223
2,535398,564
Total1,143,141
Dr. Shoemaker
1
0468,000936,000
11/16/222
03,8037,606745,577
11/16/223
2,535397,564
Total1,143,141
Mr. Hopson
1
0356,250712,500
11/16/222
03,0426,084596,415
11/16/223
2,028318,051
Total914,466
Mr. Argus
1
0356,250712,500
11/16/222
03,0426,084596,415
11/16/223
2,028318,051
Total914,466

   Estimated Possible Payouts
Under Non-Equity Incentive
Plan Awards
 




Estimated Possible Payouts
Under Equity Incentive Plan
Awards
 











All
Other
Stock Awards:
Number
of
Shares
of Stock













All Other
Option
Awards:
Number of
Securities
Underlying










Exercise
or Base
Price of
Option








Grant
Date Fair
Value of
Stock and
Option
 

Name 



Grant
Date
 



Threshold
($)
 



Target
($)
 



Maximum
($)
 



Threshold
(#)
 



Target
(#)
 



Maximum
(#)
 



or Units(1)
(#)
 



Options(1)(2)
(#)
 



Awards
($)
 



Awards
($)
 
 

Mr. Batrack

 (3)  0  1,112,400  2,224,800                      

 11/18/16                       62,599  40.80  773,098 

 11/18/16(4)           0  37,815  75,630           1,828,725 

 11/18/16(5)                    18,908        771,446 

                               3,373,269 

Mr. Burdick

 (3)  0  357,000  714,000                      

 11/18/16                       11,427  40.80  141,123 

 11/18/16(4)           0  6,903  13,806           333,781 

 11/18/16(5)                    3,451        140,801 

                               615,705 

Mr. Chu

 (3)  0  364,500  729,000                      

 11/18/16                       11,427  40.80  141,123 

 11/18/16(4)           0  6,903  13,806           333,781 

 11/18/16(5)                    3,451        140,801 

                               615,705 

Dr. Shoemaker

 (3)  0  348,750  697,500                      

 11/18/16                       11,427  40.80  141,123 

 11/18/16(4)           0  6,903  13,806           333,781 

 11/18/16(5)                    3,451        140,801 

                               615,705 

Ms. Salin

 (3)  0  205,000  410,000                      

 11/18/16                       7,552  40.080  93,267 

 11/18/16(4)           0  4,562  9,124           220,619 

 11/18/16(5)                    2,281        93,065 

                               406,951 

(1)
For our CEO, no equity awards will automatically vest upon a change in control. Instead, these awards will vest if, during the period commencing on the date of the change in control and ending on the second anniversary of such date, the executive's employment is terminated "other than for cause" or for "good reason." Upon such occurrence, all unvested stock option, restricted stock and RSU awards subject solely to time-based vesting will vest in full, and all equity awards that vest upon the achievement of performance criteria will vest based on actual performance results. For all other NEOs, equity awards made on and after November 3, 2014 will not automatically vest upon a change in control. Instead, these awards will vest if, during the period commencing on the date of the change in control and ending on the second anniversary of such date, the executive's employment is terminated "other than for cause" or for "good reason." Upon such occurrence, all unvested stock option, restricted stock and RSU awards subject solely to time-based vesting will vest in full, and all equity awards that vest upon the achievement of performance criteria will vest based on actual performance results. Only the equity awards made to the NEOs other than the CEO prior to November 3, 2014 provide for automatic vesting upon a change in control; as of the date of this proxy statement, all such awards have vested according to their normal vesting schedule. We refer you to "Potential Payments upon Termination or Change in Control" tables below for further information.
(2)
These options vest in equal annual installments on each of the first through fourth anniversaries of the grant date. The options have a maximum term of ten years subject to earlier termination in connection with cessation of service under certain circumstances. The exercise price of each option may be paid in cash or in shares of common stock valued at the closing price on the exercise date, or may be paid with the proceeds from a same-day sale of the purchased shares. For additional detail on the grant date fair value of these options, see footnote (4) of the Summary Compensation Table.
(3)
1This row represents the possible AIP awards for fiscal 2017.FY 2022. Additional information about these payments appears above in theCompensation Discussion &and Analysis section on page 37 of this proxy statement. The actual award payments, as determined by the Compensation Committee on November 17, 2017,16, 2022, are included in the "Non-EquityNon-Equity Incentive Plan Compensation"Compensation ($) column of the Summary Compensation Table.Table on page 61 of this proxy statement. The target and maximum values are calculated by multiplying: (i) 120%multiplying (a) 125% and 240%250%, respectively, by Mr. Batrack'sBatrack’s annual base salary; (ii)(b) 80% and 160%, respectively, by Mr. Burdick’s and Dr. Shoemaker’s annual base salaries; and (c) 75% and 150%, respectively, by Mr. Burdick,Argus’s and Mr. Chu and Dr. Shoemaker's respectiveHopson’s annual base salaries; and (iii) 50% and 100%, respectively, by Ms. Salin's annual base salary,salaries, each as in effect at the end of fiscal 2015. Consistent with prior fiscal years, there was no threshold value for fiscal 2017.
(4)
FY 2022.
2The amounts shown in these rowsthis row reflect, in share amounts, the threshold, target, and maximum potential awardspayouts of PSUs, as further discussed in theCompensation Discussion &and Analysis section on page 37 of this proxy statement. The PSUs cliff-vestwere granted under the 2018 Equity Incentive Program (EIP) and cliff vest in shares of our common stock after the end of a

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three-year performance period, subject to the achievement of the applicable performance goals. Vesting, from 0% to 200% of the award, is completely at risk and is based 50% upon our EPS growth and 50% upon our relative TSR. Accordingly, there is no threshold value. Dividends are payable on the underlying PSU shares. For additional detaildetails on the grant date fair value of these PSUs, see footnote (3) of the Summary Compensation Table.Table on page 61 of this proxy statement. Dividend equivalents are payable on the underlying PSU shares, but only to the extent that the applicable performance goals are subsequently satisfied and the PSUs vest.
(5)
3The amounts shown in these rowsthis row reflect the awards of RSUs, as further discussed in theCompensation Discussion &and Analysis section on page 37. of this proxy statement. The RSUs were granted under the 2015 Equity Incentive Plan2018 EIP and vest as to 25% of the award on November 18, 2023, and on each anniversary of the first through fourth anniversaries of the awardthat date until fully vested, subject to the holder'sholder’s continuous employment by us through the applicable vesting date. For additional detaildetails on the grant date fair value of these RSUs, see footnote (3) of the Summary Compensation Table.Table on page 61 of this proxy statement.


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TABLE OF CONTENTS OUTSTANDING EQUITY AWARDS AT FISCAL YEAR-END – FISCAL 2017

Executive Compensation Tables
Outstanding Equity Awards at FYE 2023
The following table provides information regarding NEO equity awards outstanding as of October 1, 2017,2023, the end of our 2017 fiscal year.

FYE 2023.
Option AwardsStock Awards
NameNumber of
Securities
underlying
Unexercised
Options
Exercisable (#)
Securities
underlying
Unexercised
Options
Unexercisable (#)
Option
Exercise
Price ($)
Option
Expiration
Date
Shares
or Units
of Stock
Not
Vested (#)
Market Value
of Shares or
Units of Stock
Not Vested ($)1
Unearned
Shares, Units,
or Other
Rights Not
Vested (#)
Market or
Payout Value
of Unearned
Shares, Units,
or Other
Rights Not
Vested ($)1
Mr. Batrack
4,2762
650,080
6,5573
996,861
8,4184
1,279,789
15,2115
2,312,528
19,6726
2,990,734
16,8377
2,559,729
22,8178
3,468,869
Total34,4625,239,25859,3269,019,332
Mr. Burdick
8142
123,752
1,4753
224,244
1,5124
229,869
2,5355
385,396
4,4266
672,885
3,0257
459,891
3,8038
578,170
Total6,336963,26211,2541,710,946
Dr. Shoemaker11,16147.9511/17/27
8142
123,752
1,4753
224,244
1,5124
229,869
2,5355
385,396
4,4266
672,885
3,0257
459,891
3,8038
578,170
Total11,1616,336963,26211,2541,710,946
Mr. Hopson
5812
88,329
1,2293
186,845
1,2334
187,453
2,0285
308,317
3,6896
560,839
2,4687
375,210
3,0428
462,475
Total5,071770,9449,1991,398,524

Tetra Tech 2024 Proxy Statement 62

Executive Compensation Tables

 
Option Awards

Stock Awards 
​ ​ ​ ​ ​ ​ ​ ​ 

Name 



Number of
Securities
Underlying
Unexercised
Options
(#)
Exercisable
 








Number of
Securities
Underlying
Unexercised
Options
(#)
Unexercisable
 








Option
Exercise
Price
($)
 





Option
Expiration
Date
 




Number of
Shares or
Units of
Stock That
Have Not
Vested (#)
 







Market Value
of Shares or
Units of
Stock That
Have Not
Vested ($)(1)
 







Number of
Unearned
Shares, Units
or Other
Rights That
Have Not
Vested (#)
 








Market or
Payout Value
of Unearned
Shares, Units
or Other
Rights That
Have Not
Vested ($)(1)
 
 

Mr. Batrack

  102,500(4)   24.26  11/16/20             

  87,191(5) 29,063  28.58  11/22/21             

  47,555(6) 47,554  27.26  11/21/22             

  24,671(7) 74,013  27.16  11/20/25             

  

(8)
 62,559  40.80  11/18/26             

              4,772(5) 222,137       

              14,386(6) 669,668       

              21,915(7) 1,020,143       

              18,908(8) 880,167       

                    57,545(9) 2,678,720 

                    58,442(10) 2,720,475 

                    37,815(11) 1,760,288 

Total:

  261,917  213,189        59,981  2,792,115  153,802  7,159,483 

Mr. Burdick

  
16,750

(2)
 

  
23.48
  
11/12/18
             

  27,500(3)   22.53  11/11/19             

  16,000(4)   24.26  11/16/20             

  17,358(5) 5,785  28.58  11/22/21             

  8,115(6) 8,114  27.26  11/21/22             

  4,406(7) 13,216  27.16  11/20/25             

  

(8)
 11,427  40.80  11/18/26             

              950(5) 44,223       

              2,454(6) 114,234       

              3,194(7) 148,681       

              3,451(8) 160,644       

                    9,819(9) 457,074 

                    10,436(10) 485,796 

                    6,903(11) 321,335 

Total:

  90,129  38,542        10,049  467,782  27,158  1,264,205 

Mr. Chu

  
36,328

(3)
 

  
22.53
  
11/11/19
             

  20,875(4)   24.26  11/16/20             

  17,358(5) 5,785  28.58  11/22/21             

  8,115(6) 8,115  27.26  11/21/22             

  4,504(7) 13,510  27.16  11/20/25             

  

(8)
 11,427  40.80  11/18/26             

              950(5) 44,223       

              2,454(6) 114,234       

              4,000(7) 186,200       

              3,451(8) 160,644       

                    9,819(9) 457,074 

                    10,668(10) 496,595 

                    6,903(11) 321,335 

Total:

  87,180  38,837        10,855  505,301  27,390  1,275,004 
Option AwardsStock Awards
NameNumber of
Securities
underlying
Unexercised
Options
Exercisable (#)
Securities
underlying
Unexercised
Options
Unexercisable (#)
Option
Exercise
Price ($)
Option
Expiration
Date
Shares
or Units
of Stock
Not
Vested (#)
Market Value
of Shares or
Units of Stock
Not Vested ($)1
Unearned
Shares, Units,
or Other
Rights Not
Vested (#)
Market or
Payout Value
of Unearned
Shares, Units,
or Other
Rights Not
Vested ($)1
Mr. Argus
5812
88,329
1,1473
174,378
1,2334
187,453
2,0285
308,317
3,4436
523,439
2,4687
375,210
3,0428
462,475
Total4,989758,4788,9531,361,125

Table of Contents

 
Option Awards

Stock Awards 
​ ​ ​ ​ ​ ​ ​ ​ 

Name 



Number of
Securities
Underlying
Unexercised
Options
(#)
Exercisable
 








Number of
Securities
Underlying
Unexercised
Options
(#)
Unexercisable
 








Option
Exercise
Price
($)
 





Option
Expiration
Date
 




Number of
Shares or
Units of
Stock That
Have Not
Vested (#)
 







Market Value
of Shares or
Units of
Stock That
Have Not
Vested ($)(1)
 







Number of
Unearned
Shares, Units
or Other
Rights That
Have Not
Vested (#)
 








Market or
Payout Value
of Unearned
Shares, Units
or Other
Rights That
Have Not
Vested ($)(1)
 
 

Dr. Shoemaker

  16,750(2)   23.48  11/12/18             

  16,750(3)   22.53  11/11/19             

  10,000(4)   24.26  11/16/20             

  10,496(5) 3,498  28.58  11/22/21             

  4,907(6) 4,906  27.26  11/21/22             

  3,916(7) 11,748  27.16  11/20/25             

  

(8)
 11,427  40.80  11/18/26             

              574(5) 26,720       

              1,484(6) 69,080       

              3,478(7) 161,901       

              3,451(8) 160,644       

                    5,937(9) 276,367 

                    9,276(10) 431,798 

                    6,903(11) 321,335 

Total:

  62,819  31,579        8,987  418,345  22,116  1,029,500 

Ms. Salin

  
16,750

(2)
 

  
23.48
  
11/12/18
             

  16,750(3)   22.53  11/11/19             

  10,000(4)   24.26  11/16/20             

  10,883(5) 3,627  28.58  11/22/21             

  5,088(6) 5,087  27.26  11/21/22             

  2,898(7) 8,693  27.16  11/20/25             

  

(8)
 7,552  40.80  11/18/26             

              595(5) 27,697       

              1,538(6) 71,594       

              2,574(7) 119,820       

              2,281(8) 106,181       

                    6,156(9) 286,562 

                    6,865(10) 319,566 

                    4,562(11) 212,361 

Total:

  62,369  24,959        6,988  325,292  17,583  818,489 

(1)
1Market value calculated based on a stock price of $46.55,$152.03, the closing price of our common stock on September 29, 2017,2023, the last trading day of our 20172023 fiscal year.
(2)
2Granted on 11/12/10;21/19; vests 25% on 11/12/1118/20 and 25% annually for next three years.
3 years.
(3)
Granted on 11/11/11;19/20; vests 25% on 11/11/1218/21 and 25% annually for next 3three years.
(4)
4Granted on 11/16/12;23/21; vests 25% on 11/16/1318/22 and 25% annually for next 3three years.
(5)
5Granted on 11/22/13;16/22; vests 25% on 11/22/1418/23 and 25% annually for next 3three years.
(6)
6Granted on 11/21/14; vests 25% on 11/21/15 and 25% annually for next 3 years.
(7)
Granted on 11/20/15; vests 25% on 11/20/16 and 25% annually for next 3 years.
(8)
Granted on 11/18/16; vests 25% on 11/18/17 and 25% annually for next 3 years.
(9)
Granted on 11/21/14; cliff-vesting19/20; cliff vesting following three-year performance period based on EPS growth and relative TSR.
(10)
7Granted on 11/20/15; cliff-vesting23/21; cliff vesting following three-year performance period based on EPS growth and relative TSR.
(11)
8Granted on 11/18/16; cliff-vesting16/22; cliff vesting following three-year performance period based on EPS growth and relative TSR.

Outstanding options under the 2015 Equity Incentive Plan (EIP) have a maximum term of ten years measured from the applicable grant date. Outstanding options under our 2005 Equity Incentive Plan have a maximum term of eight10 years measured from the applicable grant date. All options are subject to earlier termination in the event of the optionee'soptionee’s cessation of service with us under certain circumstances. The exercise price for each outstanding option is equal to the closing price per share of common stock on the grant date.


Options Exercised and Stock Vested–FY 2023

Table of Contents

OPTIONS EXERCISED AND STOCK VESTED – FISCAL 2017

The following table shows the number of shares acquired by each of the NEOs during fiscal 2017FY 2023 through exercising stock option exercisesoptions and the vesting of performance sharesPSUs and RSUs. The table also presents the value realized upon such exercisesoptions being exercised and vesting,PSUs and RSUs being vested, as calculated, in the case of stock options, based on the difference between the market price of our common stock at exercise and the option exercise price and, as calculated, in the case of performance sharesPSUs and RSUs, based on the closing price per share of our common stock on the NASDAQNasdaq Global Select Market on the vesting date.

Option AwardsStock Awards
NameShares Acquired on
Exercise (#)
Value Realized
on Exercise
($)
Shares Vested
(#)1
Value Realized
on Vesting ($)
Mr. Batrack65,95610,330,688
Mr. Burdick12,6351,979,020
Dr. Shoemaker12,6351,979,020
Mr. Hopson8,9901,408,104
Mr. Argus8,9491,401,682

 Option Awards 

Stock Awards  

Name 



Number of
Shares
Acquired on
Exercise
(#)
 






Value
Realized on
Exercise
($)
 





Number of
Shares
Vested*
(#)
 





Value
Realized
on Vesting
($)
 
 

Mr. Batrack

  320,000  6,965,039  34,405  1,456,066 

Mr. Burdick

  16,750  323,579  7,829  329,648 

Mr. Chu

  32,951  742,172  8,101  340,952 

Dr. Shoemaker

  16,750  343,178  5,119  215,048 

Ms. Salin

  16,750  350,320  4,946  208,204 

*
1Consists of PSUs and RSUs.
RSUs


Tetra Tech 2024 Proxy Statement 63

TABLE OF CONTENTS NONQUALIFIED DEFERRED COMPENSATION – FISCAL 2017

Executive Compensation Tables
Nonqualified Deferred Compensation–FY 2023
The following table shows each NEO'sNEO’s contributions and earnings during fiscal 2017FY 2023 and account balance as of October 1, 2017,2023, under our Deferred Compensation Plan.

DCP.
Name1
Executive
Contributions
in Last Fiscal
Year ($)2
Tetra Tech
Contributions
in Last Fiscal
Year ($)
Aggregate
Earnings in
Last Fiscal
Year ($)3
Aggregate
Withdrawals or
Distributions ($)4
Aggregate Balance
at Last Fiscal
Year End ($)5
Mr. Batrack120,2733,029,49321,391,326
Mr. Burdick691,915578,3005,907,992
Dr. Shoemaker564,224146,5002,053,455

Name 



Executive
Contributions
in Last Fiscal
Year ($)(1)
 





Tetra Tech
Contributions
in Last Fiscal
Year ($)
 





Aggregate
Earnings in
Last Fiscal
Year ($)(2)
 





Aggregate
Withdrawals or
Distributions
($)
 





Aggregate
Balance at
Last Fiscal
Year-End ($)(3)
 
 

Mr. Batrack

  1,443,248    272,866  800,620  4,709,555 

Mr. Burdick

  154,616    362,987    2,642,310 

Mr. Chu

  153,358    101,118    1,263,112 

Dr. Shoemaker

      90,487    671,710 

Ms. Salin

      137,476    1,096,171 

1 Mr. Hopson and Mr. Argus are not included in this table because they do not participate in the DCP.
(1)
2These amounts were included in the "Salary"Salary ($) and/or "Non-EquityNon-Equity Incentive Plan Compensation"Compensation ($) columns, as applicable, of the Summary Compensation Table.
(2)
Table on page 61 of this proxy statement.
3None of the amounts are included in the Summary Compensation Table on page 61 of this proxy statement because plan earnings were not preferential or above-market.
(3)
Noneabove market. The amount for Mr. Batrack includes $2,824,348, representing the stock price appreciation of Tetra Tech stock units deferred into the DCP. There is no guarantee that the earnings associated with the deferred Tetra Tech stock units will be realized by Mr. Batrack.
4 These amounts arewere included in the Salary ($) and/or Non-Equity Incentive Plan Compensation ($) columns, as applicable, of the Summary Compensation Table because we did not make any contributions toon page 61 of this proxy statement at the Deferred Compensation Plan during fiscal 2017.time such compensation was earned.

5 As of September 29, 2023, which was the last business day of FY 2023. The Deferred Compensation Planamount for Mr. Batrack includes $18,271,726, representing the value of Tetra Tech stock units deferred into the DCP.
The DCP is an unfunded and unsecured deferred compensation arrangement that is designed to allow the participants to defer a percentage of their base salary, bonuses, non-employee directordirector’s fees, and equity awards other than options and invest the deferrals in a manner similar to the way in which our 401(k) plan operates, but without regard to the maximum deferral limitations imposed on 401(k) plans by the Internal Revenue Code. The Deferred Compensation PlanDCP is designed to comply with Section 409A of the Internal Revenue Code. As required by applicable law, participation in the Deferred Compensation PlanDCP is limited to our directors and a group of our management employees, which group includes each of our NEOs. Since the adoption of the Deferred Compensation PlanDCP by the Board of Directors in 2006, we have not made any contribution on behalf of any director or executive officer.


Table of Contents

Amounts deferred by each participant pursuant to the Deferred Compensation PlanDCP are credited to a bookkeeping account maintained on behalf of that participant. Amounts credited to each participant under the Deferred Compensation PlanDCP are periodically adjusted for earnings and/or losses at a rate that isrates equal to one or more of the measurement funds selected by the Deferred Compensation Plan Committee and elected by a participant.

POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

participants. Stock unit deferrals represent shares of Tetra Tech common stock and may not be diversified into other investment options.

Potential Payments upon Termination or Change in Control
We do not enter into employment agreements with our NEOs (or any executive officers). The CEO'sCEO’s employment may be terminated at any time at the discretion of the Board of Directors. The employment of the other NEOs may be terminated at any time by the CEO with the Board'sBoard’s concurrence.

              We have entered into Our NEOs are eligible to participate in the CIC Severance Plan.

Under the CIC Severance Plan, if an amended and restated change in control agreement with each of our NEOs, which terminate on March 25, 2018. The agreements provide that if the NEO'sNEO’s employment is terminated by us "other than for cause"“without cause” or by the NEO with "good“with good reason," in each case, within two years following (or, in the case of a termination without cause, a 90-day period immediately preceding) a change in control that occurs during the term of the agreement,(each, a “qualifying termination”), we will pay or provide the following lump sum cash severance benefits:

      payments:
severance
Severance pay equal to $4,078,800, subject to adjustmenttheir current base salary plus a target bonus for salary changes (inthe fiscal year employment terminates times a multiple (2.0 in the case of Mr. Batrack), 175% of base salary (inBatrack, 1.5 in the casecases of Mr. Burdick Mr. Chu and Dr. Shoemaker),Shoemaker, and 150%1.0 in the cases of base salary (in the case of Ms. Salin);

Messrs. Hopson and Argus)
a pro-rata
A pro rata target bonus for the year of termination, based on actual performance and the number of days the NEO worked during the year;

year
the
The bonus the NEO earned for the year preceding the year of termination if such bonus hadhas not yet been paid; and

paid
a
A payment equal to 102% of the cost of providing one year of healthmedical benefits (health, dental, and vision) to the NEO and his or hertheir dependents substantially similar to those provided immediately prior to such termination date.

date for 24 months (in the case of the Mr. Batrack), 18 months (in the cases of Mr. Burdick and Dr. Shoemaker), or 12 months (in the cases of Messrs. Hopson and Argus)

In addition, pursuant to the terms of the CIC Severance Plan, in connection with a qualifying termination, all outstanding and unvested stock options, restricted stock, and RSUs that vest solely based on continued employment will fully vest, and equity awards

Tetra Tech 2024 Proxy Statement 64

Executive Compensation Tables
that vest in whole or in part on achievement of performance criteria will vest based on actual performance results. No outstanding or unvested equity awards held by our NEOs will automatically vest upon a change in control.
Under the terms of the change in control agreements,CIC Severance Plan, if an NEO'sNEO’s employment is terminated due to his or herbecause of their death or disability, in each case, within two years following a change in control, that occurs during the term of the agreement, we will pay a pro-ratapro rata target bonus for the year of termination, based on actual performance and the number of days the NEO worked during the year, together with the bonus the NEO earned for the year preceding the year of termination if such bonus hadhas not yet been paid.

All severance payments described above are contingent on the execution of a release and continued compliance with the restrictive covenants set forth in the CIC Severance Plan (i.e., confidentiality and non-solicitation of employees, clients, suppliers, licensees, or business relations for a post termination period of 24 months for Mr. Batrack, 18 months for Mr. Burdick and Dr. Shoemaker, and 12 months for Messrs. Hopson and Argus).
Each NEO will also be paid or provided with any unpaid base salary, accrued vacation, and unreimbursed expenses through the date of his or hertheir employment termination, together with any benefits to which the NEO is entitled under our benefits programs.

              For our CEO, effective November 7, 2016, no equity awards will automatically vest upon a change in control. Instead, these awards will vest if, during the period commencing on the date of the change in control and ending on the second anniversary of such date, the executive's employment is terminated by us "other than for cause" or by the CEO for "good reason." Upon such occurrence, all unvested equity awards subject solely to time-based vesting will vest in full, and all equity awards that vest upon the achievement of performance criteria will vest based on actual performance results. For all other NEOs, equity awards made on and after November 3, 2014 will not automatically vest upon a change in control. Instead, these awards will vest if, during the period commencing on the date of the change in control and ending on the second anniversary of such date, the executive's employment is


Table of Contents

terminated "other than for cause" or for "good reason." Upon such occurrence, all unvested equity awards subject solely to time-based vesting will vest in full, and all equity awards that vest upon the achievement of performance criteria will vest based on actual performance results. Equity awards made to the NEOs other than the CEO prior to November 3, 2014 provide for automatic vesting upon a change in control, regardless of whether any applicable performance targets have been met; as of the date of this proxy statement, all such awards have vested according to their normal vesting schedule.

The payments and benefits described aboveprovided for under the CIC Severance Plan will be reduced to the extent that they would result in triggeringtrigger excise taxes under Section 4999 of the Internal Revenue Code, (or be within $1,000 of doing so), unless thean NEO would be better off by at least $50,000 on an after-tax basis, after taking into account all taxes, and receiving the full amount of the payments and benefits, in whichbenefits. In that case, the NEO will receive the full amount of his or her payments and benefits.benefits will not be reduced. In no event are weis the Company obligated to provide any tax gross-upgross up or similar payment to cover any NEO's Section 4999 excise tax.

the NEOs.

A "change“change in control"control” for purposes of the change in control agreementsCIC Severance Plan generally consists of one or more of the following events:

an
An acquisition by any person of beneficial ownership of securities representing 50% or more of the combined voting power of ourTetra Tech’s voting securities (on one date or during any 12-month period);

the
The consummation of a merger, reorganization, or consolidation if ourTetra Tech’s stockholders (together with any trustee or fiduciary acquiring securities under any benefit plan) do not own more than 50% of the combined voting power of the merged, company's then-outstandingreorganized, or consolidated Company’s then outstanding securities (other than a recapitalization in which no person acquires more than 50% of the combined voting power of our outstanding securities); or


The consummation of a sale of all or substantially all of ourTetra Tech’s assets (other than a sale to an entity in which our stockholders own 50% or more of the voting securities of such entity).

              "Good reason"

“Good reason” for purposes of the change in control agreementsCIC Severance Plan generally includes any of the following actions by us:

      Tetra Tech:
a
A material diminution of the NEO'sNEO’s base salary, annual bonus opportunity, or both;

both
a
A material diminution in the NEO'sNEO’s authority, duties, or responsibilities;

responsibilities
a material diminution in the authority, duties or responsibilities of the supervisor to whom the NEO is required to report;

a
A material diminution in the budget over which the NEO retains authority; or

authority
a
A material change in the geographic location at which the NEO must perform his or her services.

their services

An NEO will only be entitled to terminate his or hertheir employment for good reason only if he or she hasthey have provided usTetra Tech with notice of the occurrence of a condition described above within 60 days of its initial existence and we have failed to remedy such condition within 30 days after receipt of the notice. An NEO'sNEO’s employment will be deemed to have been terminated following a change in control by the NEO for good reason if the NEO terminates his or hertheir employment prior to a change in control for good reason if a


Table of Contents

good reason condition occurs at the direction of a person or entity who has entered into an agreement with us,Tetra Tech, the consummation of which will constitute a change in control.

              "Cause" means:

“Cause” means one of the following:
the
The willful and continued failure of the NEO to perform substantially his or hertheir duties (other than a failure resulting from incapacity due to physical or mental illness), after a written demand for substantial performance is delivered to the NEO by the boardBoard of directorsDirectors or chief executive officerCEO that specifically identifies the manner in which the boardBoard of directorsDirectors or chief executive officerCEO believes that the NEO has not substantially performed his or her duties; or

their duties
the
The willful engaging by the NEO in illegal conduct or gross misconduct that is materially and demonstrably injurious to the company.

Company

For purposes of this definition of "cause"“cause,” no act or failure to act on the part of an NEO will be considered "willful"“willful” unless it is done, or omitted to beis not done, by the NEO in bad faith or without reasonablyreasonable belief that the NEO'sNEO’s action or omission was in the ourTetra Tech’s best interests. Any act, or failure to act, based upon authority given pursuant to a resolution duly adopted by the boardBoard of directorsDirectors or

Tetra Tech 2024 Proxy Statement 65

Executive Compensation Tables
upon the instructions of our chief executive officer orCEO, one of our seniorexecutive officers or based upon the advice of our legal counsel will be conclusively presumed to be done, or omitted to benot done, by the NEO in good faith and in our best interests.

Assumptions Regarding the Tables

The tables belowin this section were prepared as though a change in control occurred on September 29, 20172023 (the last business day of ourTetra Tech’s most recent fiscal year), and the employment of each of our NEOs was terminated on thisthat date. For purposes of any calculations involving equity awards, we have used the closing share price of ourTetra Tech common stock on September 29, 2017 (the last business day of our fiscal year),2023, which was $46.55. We are$152.03. Tetra Tech is required by the SEC to use these assumptions. However, the NEOs'The NEOs’ employment was not terminated on September 29, 2017,2023, however, and a change in control did not occur on thisthat date. As a result, there can be no assurance that a termination of employment, a change in control, or both would produce the same or similar results as those described if either or both of them occuroccurred on any other date or at any other price, or if any assumption used in this disclosure is not correct in fact. All amounts set forthpresented in the tables below are estimates only. The following are the equity award and annual bonus assumptions:

stock
Stock options that vest due to a change in control or an employment termination "other than for cause"“without cause” or for "good reason"“with good reason” within two years following (or, in the case of a termination without cause, 90 days immediately preceding) a change in control are valued based on their option spread (i.e., the excess of fair market value of a share of common stock on September 29, 2017 (i.e., $46.55)2023, $152.03 over the exercise price);


PSUs and RSUs that vest due to a change in control or an employment termination "other than for cause"“without cause” or for "good reason"“with good reason” within two years following (or, in the case of a termination without cause, 90 days immediately preceding) a change in control are valued based on the number of shares subject to such award multiplied by the fair market value of a share of common stock on September 29, 2017 (i.e. $46.55);

2023 ($152.03)

PSUs are assumed to vest at 100% of target; and

target
given
Given that each of the NEO'sNEO’s employment is assumed to have been terminated on September 29, 20172023, for purposes of the tables below,in this section, any annual bonus with respect to suchfor that year would have been earned as of suchthat date under the terms of ourTetra Tech’s bonus program. As such,a result, no amounts with respect to pro-ratedprorated bonuses for the year of termination of employment have been included in the tables below.


Tetra Tech 2024 Proxy Statement 66

Executive Compensation Tables
Dan L. Batrack

Payment TypeChange in
Control
($)
Termination without Cause
or with Good Reason in
Connection with a
Change in Control ($)
Termination Due to
Death or Disability in
Connection with a
Change in Control ($)
1
Termination Due to
Resignation without
Good Reason in
Connection with a
Change in Control ($)
2
Termination Due to
Cause in Connection
with a Change in
Control ($)
2

​Change in
Control ($)(1)




Termination
Without Cause
or With Good
Reason
Following a
Change in
Control ($)









Termination
Due to
Death or
Disability
Following a
Change in
Control
($)(2)










Termination
Due to
Resignation
Without
Good
Reason
Following a
Change in
Control
($)(3)












Termination
Due to
Cause
Following a
Change in
Control
($)(3)

Severance Benefits(4)

3
4,078,8005,280,000

Pro-Rated

Prorated Bonus

Health Benefits

24,00029,184

Accelerated Vesting of Unvested Stock Options(5)

4
3,234,654

Accelerated Vesting of Unvested Performance Shares/PSUs(5)

7,159,483

Accelerated Vesting of Unvested RSUs(5)

2,792,115

Golden Parachute Cut-back (if any)

(4,171,500)

Total

13,117,552
49,019,332
Accelerated Vesting of Unvested RSUs4
5,239,410
Golden Parachute Cutback (if any)
Total19,567,926

(1)
On November 7, 2016, we entered into an amended and restated change in control agreement with Mr. Batrack providing that unvested equity will not automatically vest on a change in control. Rather, a termination of employment without cause or with good reason within two years following a change in control is also required.
(2)
1The only cash compensation payable is the pro-ratedprorated bonus, together with the bonus earned from the prior year if not yet paid, and any unpaid base salary through the date of termination. Othertermination, and other payments available from life insurance or disability plans.
(3)
2The only cash compensation payable is any unpaid base salary through the date of termination.
(4)
3Payable in a cash lump sum payment.
(5)
4Does not include the value associated with options to purchase our common stock, performance shares, and RSUs that were vested as of September 29, 2017.2023. No PSUs were vested as of that date. Other than with respect to amounts under "Termination Withoutin the Termination without Cause or Withwith Good Reason Followingin Connection with a Change in Control" ($) column, does not include any unvested securities.securities issued subsequent to November 3, 2014. See "Outstandingthe Outstanding Equity Awards at Fiscal Year-End – Fiscal 2017"FYE 2023 section on page 63 of this proxy statement for information regarding outstanding vested stock options. See "Optionsthe Options Exercised and Stock Vested – Fiscal 2017"Vested—FY 2023 section on page 64 of this proxy statement for information regarding performance shares and RSUs that vested in fiscal 2017.FY 2023.

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Steven M. Burdick

Payment TypeChange in
Control
($)
Termination without Cause
or with Good Reason in
Connection with a
Change in Control ($)
Termination Due to
Death or Disability in
Connection with a
Change in Control ($)
1
Termination Due to
Resignation without
Good Reason in
Connection with a
Change in Control ($)
2
Termination Due to
Cause in Connection
with a Change in
Control ($)
2
Severance Benefits3
1,093,750
Prorated Bonus
Health Benefits14,400
Accelerated Vesting of Unvested Stock Options4
Accelerated Vesting of Unvested Performance Shares/PSUs4
1,710,946
Accelerated Vesting of Unvested RSUs4
963,566
Golden Parachute Cutback (if any)
Total3,782,662

 ​Change in
Control
($)(1)
 




Termination
Without Cause
or With Good
Reason
Following a
Change in
Control ($)
 








Termination
Due to
Death or
Disability
Following a
Change in
Control
($)(2)
 









Termination
Due to
Resignation
Without
Good
Reason
Following a
Change in
Control
($)(3)
 











Termination
Due to
Cause
Following a
Change in
Control
($)(3)
 
 

Severance Benefits(4)

    833,000       

Pro-Rated Bonus

           

Health Benefits

    24,000       

Accelerated Vesting of Unvested Stock Options(5)

  103,970  582,472       

Accelerated Vesting of Unvested Performance Shares/PSUs(5)

    1,264,205       

Accelerated Vesting of Unvested RSUs(5)

  44,223  467,782       

Golden Parachute Cut-back (if any)

          
 

Total

  148,193  3,171,459      
 

(1)
Represents cash value of equity awards granted before November 3, 2014, the vesting of which would have accelerated in full had a change in control occurred on September 29, 2017.
(2)
1The only cash compensation payable is the pro-ratedprorated bonus, together with the bonus earned from the prior year if not yet paid, and any unpaid base salary through the date of termination. Othertermination, and other payments available from life insurance or disability plans.
(3)
2The only cash compensation payable is any unpaid base salary through the date of termination.
(4)
3Payable in a cash lump sum payment.
(5)
4Does not include the value associated with options to purchase our common stock, performance shares, and RSUs that were vested as of September 29, 2017.2023. No PSUs were vested as of that date. Other than with respect to amounts under "Termination Withoutin the Termination without Cause or Withwith Good Reason Followingin Connection with a Change in Control" ($) column, does not include unvested securities issued subsequent to November 3, 2014. See "Outstandingthe Outstanding Equity Awards at Fiscal Year-End – Fiscal 2017"FYE 2023 section on page 63 of this proxy statement for information regarding outstanding vested stock options. See "Optionsthe Options Exercised and Stock Vested – Fiscal 2017"Vested—FY 2023 section on page 64 of this proxy statement for information regarding performance shares and RSUs that vested in fiscal 2017.FY 2023.


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Ronald J. Chu

Tetra Tech 2024 Proxy Statement 67

 ​Change in
Control
($)(1)
 




Termination
Without Cause
or With Good
Reason
Following a
Change in
Control ($)
 








Termination
Due to
Death or
Disability
Following a
Change in
Control
($)(2)
 









Termination
Due to
Resignation
Without
Good
Reason
Following a
Change in
Control
($)(3)
 











Termination
Due to
Cause
Following a
Change in
Control
($)(3)
 
 

Severance Benefits(4)

    850,500       

Pro-Rated Bonus

           

Health Benefits

    24,000       

Accelerated Vesting of Unvested Stock Options(5)

  103,970  588,172       

Accelerated Vesting of Unvested Performance Shares/PSUs(5)

    1,275,004       

Accelerated Vesting of Unvested RSUs(5)

  44,223  505,301       

Golden Parachute Cut-back (if any)

          
 

Total

  148,193  3,242,977      
 

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(1)
Represents cash value of equity awards granted before November 3, 2014, the vesting of which would have accelerated in full had a change in control occurred on September 29, 2017.
(2)
Executive Compensation Tables
Leslie L. Shoemaker
Payment TypeChange in
Control
($)
Termination without Cause
or with Good Reason in
Connection with a
Change in Control ($)
Termination Due to
Death or Disability in
Connection with a
Change in Control ($)
1
Termination Due to
Resignation without
Good Reason in
Connection with a
Change in Control ($)
2
Termination Due to
Cause in Connection
with a Change in
Control ($)
2
Severance Benefits3
1,023,750
Prorated Bonus
Health Benefits14,376
Accelerated Vesting of Unvested Stock Options4
Accelerated Vesting of Unvested Performance Shares/PSUs4
1,710,946
Accelerated Vesting of Unvested RSUs4
963,566
Golden Parachute Cutback (if any)
Total3,712,638
1The only cash compensation payable is the pro-ratedprorated bonus, together with the bonus earned from the prior year if not yet paid, and any unpaid base salary through the date of termination. Othertermination, and other payments available from life insurance or disability plans.
(3)
2The only cash compensation payable is any unpaid base salary through the date of termination.
(4)
3Payable in a cash lump sum payment.
(5)
4Does not include the value associated with options to purchase our common stock, performance shares, and RSUs that were vested as of September 29, 2017.2023. No PSUs were vested as of that date. Other than with respect to amounts under "Termination Withoutin the Termination without Cause or Withwith Good Reason Followingin Connection with a Change in Control" ($) column, does not include unvested securities issued subsequent to November 3, 2014. See "Outstandingthe Outstanding Equity Awards at Fiscal Year-End – Fiscal 2017"FYE 2023 section on page 63 of this proxy statement for information regarding outstanding vested stock options. See "Optionsthe Options Exercised and Stock Vested – Fiscal 2017"Vested—FY 2023 section on page 64 of this proxy statement for information regarding performance shares and RSUs that vested in fiscal 2017.FY 2023.

Preston Hopson

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Leslie L. Shoemaker

Payment TypeChange in
Control
($)
Termination without Cause
or with Good Reason in
Connection with a
Change in Control ($)
Termination Due to
Death or Disability in
Connection with a
Change in Control ($)
1
Termination Due to
Resignation without
Good Reason in
Connection with a
Change in Control ($)
2
Termination Due to
Cause in Connection
with a Change in
Control ($)
2
Severance Benefits3
892,500
Prorated Bonus
Health Benefits6,720
Accelerated Vesting of Unvested Stock Options4
Accelerated Vesting of Unvested Performance Shares/PSUs4
1,398,524
Accelerated Vesting of Unvested RSUs4
771,248
Golden Parachute Cutback (if any)
Total3,068,992

 ​Change in
Control
($)(1)
 




Termination
Without Cause
or With Good
Reason
Following a
Change in
Control ($)
 








Termination
Due to
Death or
Disability
Following a
Change in
Control
($)(2)
 









Termination
Due to
Resignation
Without
Good
Reason
Following a
Change in
Control
($)(3)
 











Termination
Due to
Cause
Following a
Change in
Control
($)(3)
 
 

Severance Benefits(4)

    813,750       

Pro-Rated Bonus

           

Health Benefits

    24,000       

Accelerated Vesting of Unvested Stock Options(5)

  62,868  451,013       

Accelerated Vesting of Unvested Performance Shares/PSUs(5)

    1,029,500       

Accelerated Vesting of Unvested RSUs(5)

  26,720  418,345       

Golden Parachute Cut-back (if any)

          
 

Total

  89,588  2,736,608      
 

(1)
Represents cash value of equity awards granted before November 3, 2014, the vesting of which would have accelerated in full had a change in control occurred on September 29, 2017.
(2)
1The only cash compensation payable is the pro-ratedprorated bonus, together with the bonus earned from the prior year if not yet paid, and any unpaid base salary through the date of termination. Othertermination, and other payments available from life insurance or disability plans.
(3)
2The only cash compensation payable is any unpaid base salary through the date of termination.
(4)
3Payable in a cash lump sum payment.
(5)
4Does not include the value associated with options to purchase our common stock, performance shares, and RSUs that were vested as of September 29, 2017.2023. No PSUs were vested as of that date. Other than with respect to amounts under "Termination Withoutin the Termination without Cause or Withwith Good Reason Followingin Connection with a Change in Control" ($) column, does not include unvested securities issued subsequent to November 3, 2014. See "Outstandingthe Outstanding Equity Awards at Fiscal Year-End – Fiscal 2017"FYE 2023 section on page 63 of this proxy statement for information regarding outstanding vested stock options. See "Optionsthe Options Exercised and Stock Vested – Fiscal 2017"Vested—FY 2023 section on page 64 of this proxy statement for information regarding performance shares and RSUs that vested in fiscal 2017.FY 2023.


Table of Contents

Janis B. Salin

Tetra Tech 2024 Proxy Statement 68

 ​Change in
Control
($)(1)
 




Termination
Without Cause
or With Good
Reason
Following a
Change in
Control ($)
 








Termination
Due to
Death or
Disability
Following a
Change in
Control
($)(2)
 









Termination
Due to
Resignation
Without
Good
Reason
Following a
Change in
Control
($)(3)
 











Termination
Due to
Cause
Following a
Change in
Control
($)(3)
 
 

Severance Benefits(4)

    615,000       

Pro-Rated Bonus

           

Health Benefits

    24,000       

Accelerated Vesting of Unvested Stock Options(5)

  65,286  375,310       

Accelerated Vesting of Unvested Performance Shares/PSUs(5)

    818,489       

Accelerated Vesting of Unvested RSUs(5)

  27,697  325,361       

Golden Parachute Cut-back (if any)

          
 

Total

  92,983  2,158,160      
 

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(1)
Represents cash value of equity awards granted before November 3, 2014, the vesting of which would have accelerated in full had a change in control occurred on September 29, 2016.
(2)
Executive Compensation Tables
Roger R. Argus
Payment TypeChange in
Control
($)
Termination without Cause
or with Good Reason in
Connection with a
Change in Control ($)
Termination Due to
Death or Disability in
Connection with a
Change in Control ($)
1
Termination Due to
Resignation without
Good Reason in
Connection with a
Change in Control ($)
2
Termination Due to
Cause in Connection
with a Change in
Control ($)
2
Severance Benefits3
892,500
Prorated Bonus
Health Benefits17,460
Accelerated Vesting of Unvested Stock Options4
0
Accelerated Vesting of Unvested Performance Shares/PSUs4
1,361,125
Accelerated Vesting of Unvested RSUs4
758,630
Golden Parachute Cutback
(if any)
Total3,029,715
1The only cash compensation payable is the pro-ratedprorated bonus, together with the bonus earned from the prior year if not yet paid, and any unpaid base salary through the date of termination. Othertermination and other payments available from life insurance or disability plans.
(3)
2The only cash compensation payable is any unpaid base salary through the date of termination.
(4)
3Payable in a cash lump sum payment.
(5)
4Does not include the value associated with options to purchase our common stock, performance shares, and RSUs that were vested as of September 29, 2017.2023. No PSUs were vested as of that date. Other than with respect to amounts under "Termination Withoutin the Termination without Cause or Withwith Good Reason Followingin Connection with a Change in Control" ($) column, does not include unvested securities issued subsequent to November 3, 2014. See "Outstandingthe Outstanding Equity Awards at Fiscal Year-End – Fiscal 2017"FYE 2023 section on page 63 of this proxy statement for information regarding outstanding vested stock options. See "Optionsthe Options Exercised and Stock Vested – Fiscal 2017"Vested—FY 2023 section on page 64 of this proxy statement for information regarding performance shares and RSUs that vested in fiscal 2017.FY 2023.

Equity Compensation Plan Information

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EQUITY COMPENSATION PLAN INFORMATION

The following table provides information as of October 1, 2017 with respect to2023, about the shares of ourTetra Tech common stock that may be issued under our existing equity compensation plans under which awards may be granted.plans. All of our existing plans have been approved by our stockholders. A majority of our employees are eligible to participate in the Employee Stock Purchase Plan (ESPP) and the 2015 Equity Incentive Plan (2015 Plan),2018 EIP, subject to certain limitations, terms, and conditions.

Equity Compensation Plans Approved by Stockholders1
Securities to be Issued upon Exercise
of Outstanding Options, Warrants,
and Rights (#)2
Weighted Average Exercise Price
of Outstanding Options, Warrants,
and Rights3
Securities Remaining Available for
Future Issuance under Equity
Compensation Plans (excluding
securities reflected in the first
column) (#)
148,400$39.45
4,710,8744

 A  B  C 

 ​Number of Securities to
be Issued Upon
Exercise of
Outstanding Options(1)
 





Weighted Average
Exercise Price of
Outstanding Options
 




Number of
Securities
Remaining
Available for Future
Issuance Under
Equity
Compensation
Plans (Excluding
Securities Reflected
in
Column A)
 

Equity Compensation Plans Approved by Stockholders(2)

 1,752,933 27.18 3,713,530(3)

1 Consists of the 2018 EIP, the 2015 EIP (under which options and awards are no longer granted), and the ESPP.
(1)
2Excludes purchase rights under our ESPP for the purchase right period that commenced on January 1, 20172023, and ended on December 15, 2017.
(2)
Consists of the 2015 Plan, the 2005 Equity Incentive Plan (under which awards are no longer granted), the 2003 Outside Director Stock Option Plan (under which options are no longer granted) and the ESPP. If Proposal No. 3 is approved, we will no longer grant awards under the 2015 Plan.
(3)
As of October 1, 2017, an aggregate of 2,644,111, 0, 0 and 1,069,4192023. Excludes 137,759 deferred, vested rights to receive shares of common stock were available for issuance under the 2015 Plan, the 2005 Equity Incentive Plan, the 2003 Outside Director Stock Option Plan and the ESPP, respectively.

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ITEM 3 – APPROVAL OF THE 2018 EQUITY INCENTIVE PLAN

              At our annual meeting, stockholders will be askedpursuant to approve the 2018 Equity Incentive Plan (2018 Plan), which was adopted, subject to stockholder approval, by the Board on November 6, 2017.

              We currently maintain the Tetra Tech Inc. 2015 Equity Incentive Plan (2015 Plan) andDCP.

3 Represents the Tetra Tech, Inc. Employee Stock Purchase Plan.

              If stockholders approve the 2018 Plan, no new awards will be granted under the 2015 Plan following the annual meeting. The total number of shares that will be made available for award grants under the 2018 Plan will be 3,000,000 shares. Any shares subject to outstanding awards under our existing equity plans that expire, are cancelled or otherwise terminate, or that are exchanged or withheld to pay the purchase price orweighted average exercise price of an award or to satisfy tax withholding obligations at any time after the annual meeting will not be available for award grant purposes under the 2018 Plan.

              If stockholders do not approve the 2018 Plan, we will continue to have the authority to grant equity-based awards under the 2015 Plan. If stockholders approve the 2018 Plan, the terminationoutstanding stock options only.

4 Consists of our grant authority under the 2015 Plan will not affect awards then outstanding under the 2015 Plan.

              The Board believes that our success depends in part on being able to attract, retain and reward our employees and service providers, and strengthen the link between stockholder and award holder interests. The Board approved the 2018 Plan based in part on a belief that the number of1,765,385 shares currently available under the 2015 Plan and the structure of its share reserve do not give us sufficient authority and flexibility to adequately provide for future incentives beyond 2018. The Board believes that the 2018 Plan reflects an appropriate balance between providing us with the flexibility to continue our equity award program over a multi-year period and stockholder dilution concerns.

DESCRIPTION OF THE 2018 PLAN

              The following is a summary of the principal features of the 2018 Plan. This summary does not purport to be a complete description of all of the provisions of the 2018 Plan. It is qualified in its entirety by reference to the full text of the 2018 Plan. A copy of the 2018 Plan is attached to this proxy statement as Appendix A.

Share Reserve

              The maximum number ofEIP, 2,663,139 shares that may be issued or transferred pursuant to equity awardsavailable under the 2018 Plan will equal 3,000,000. We may satisfy our obligationsEIP, and 282,350 shares available under any awards grantedthe ESPP. Shares available under the 2018 PlanEIP can be used for any type of award available under that plan, including options, restricted stock, and RSU awards.


Tetra Tech 2024 Proxy Statement 69

Executive Compensation Tables
Pay Ratio Disclosure
As required by issuing new shares or treasury shares.

              The following rules apply for counting shares against the applicable share limitsSection 953(b) of the 2018 Plan:

      Any shares related to awards that terminate by expiration, forfeiture, cancellation or otherwise without the issuanceDodd Frank Wall Street Reform and Consumer Protection Act (Dodd-Frank Act) and Item 402(u) of such shares, are settled in cash in lieu of shares, or are exchanged without the Compensation Committee's permission, prior to the issuance of shares, for awards not involving shares, shall be available again for grantRegulation S K under the 2018 Plan.

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      The full number of stock options and SARs granted that are to be settled bySecurities Act, Tetra Tech is providing the issuance of shares shall be counted againstfollowing information about the number of shares available for award under the 2018 Plan, regardlessrelationship of the numberannual total compensation of shares actually issuedour employees (excluding our CEO) and the annual total compensation of Mr. Batrack, our Chairman of the Board and CEO. The pay ratio was calculated in a manner consistent with Item 402(u) of Regulation S K and based upon settlementour reasonable judgment and assumptions. For FY 2023, CEO compensation, which was earned but not realized, was $10,331,897, the median employee compensation (excluding our CEO) was $97,648.35 and our estimate of any such award.

      Any shares withheldthe CEO pay ratio was 106.
To determine the median employee compensation, we reviewed compensation data from the Tetra Tech global employee population on July 1, 2023.This global population on July 1, 2023, was 19,975. The U.S. portion of this population was 10,396. For purposes of determining the median employee compensation, 982 international employees were excluded.1 After exclusions, the total population from which the median employee compensation was determined was 18,993. To identify the median employee compensation, earnings figures for the 39-week period of October 1, 2022, through July 1, 2023, were collected. Non-U.S. dollar earnings were converted to satisfy tax withholding obligationsU.S. dollars based on an award issued under the 2018 Plan, shares tendered to pay the exercise priceexchange rate on July 1, 2023. For employees who worked a partial year because of a stock option, and shares repurchased onhire date that fell after the open market with the proceeds of a stock option exercise will not be eligible to be again available for grant under the 2018 Plan.

Maximum Individual Limits

              The 2018 Plan imposes annual per-participant award limits for participants. The annual per-participant limits are as follows: (i) no more than 500,000 shares may be granted as incentive stock options to any single participant during a single calendar year; (ii) no more than 1,000,000 shares may be subject to stock options and SARs to any single participant during a single calendar year; and (iii) no more than 500,000 shares may be subject to performance compensation awards (excluding stock options and SARs) to any single participant during a single calendar year (or, in the event such performance compensation award is paid in cash, other securities, other awards, or other property, no more than the fair market value of 500,000 shares on the last daystart of the performance period to which such performance compensation award relates).

              The amount of the unused annual limit with respect to the previous calendarfiscal year, under the 2018 Plan beginning on or after January 1, 2019earnings were annualized. Earnings were not annualized for an award denominated in shares shall be added to the maximum applicable per-participant share limit.

Corporate Governance Aspect of the 2018 Plan

              The 2018 Plan includes several provisions that we believe promote best practices by reinforcing alignment with stockholders' interests. These provisions include, but are not limited to, the following:

      No Discounted Stock Options or SARs:  Stock options and SARs may not be granted with exercise prices or strike prices less than the fair market value of the underlying shares on the grant date, except to replace equity awards due to a corporate transaction.

      No Repricing without Stockholder Approval:  Other than in connection with corporate reorganizations or restructurings, at any time when the exercise price of a stock option or strike price of a SARcasual employees.
This information is above the market value of a share, we will not, without stockholder approval, reduce the exercise price of such stock option or strike price of such SAR and will not exchange such stock option or SARbeing provided for a new award with a lower (or no) purchase price or for cash.

No Transferability:  Equity awards generally may not be transferred, except by will or the laws of descent and distribution, unless approved by the Compensation Committee.

No Evergreen Provisions:  The 2018 Plan does not contain an "evergreen" feature pursuant to which the shares authorized under the 2018 Plan can be automatically replenished.

No Automatic Grants:  The 2018 Plan does not provide for automatic grants to any participants.

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Section 162(m) – Performance Based Compensation

              The Board approved the 2018 Plan before the Tax Cuts and Jobs Act was signed into law on December 22, 2017. Accordingly, the 2018 Plan is structured in such a manner so that, in the absence of the changes to the law made by the Tax Cuts and Jobs Act,compliance purposes. Neither the Compensation Committee could have,nor our management used the pay ratio measure in its sole discretion, electedmaking compensation decisions. Given the different methodologies that companies use to grant equity awards that satisfieddetermine an estimate of their pay ratio, the requirements of "performance-based compensation" within the meaning of Section 162(m) of the Internal Revenue Code, as it existed prior to passage of the Tax Cuts and Jobs Act. The Tax Cuts and Jobs Act eliminated the "performance-based compensation" exemption under Section 162(m) with respect to taxable years beginning after December 31, 2017 (unless the compensation is provided pursuant to a written binding contract which was in effect on November 2, 2017, and which was not modified in any material respect on or after November 2, 2017). Pursuant to the "performance-based compensation" exemption, public companies could preserve the deductibility of compensation paid to certain executive officers in excess of $1 million, so long as that compensation qualified as "performance-based compensation" under Section 162(m). The elimination of the "performance-based compensation" exemption under Section 162(m), together with other amendments to Section 162(m) included in the Tax Cuts and Jobs Act, means that, effective with respect to taxable years beginning after December 31, 2017, we will no longer be able to deduct compensation in excess of $1 million paid in any one year to our CEO, any of our other named executive officers, or any employee who was our CEO or one of our other named executive officers for any preceding taxable year beginning with fiscal 2017 (other than any officer who is not subject to U.S. income tax) on the grounds that such compensation qualifies as "performance-based" (unless the compensation is provided pursuant to a written binding contract which was in effect on November 2, 2017, and which was not modified in any material respect on or after November 2, 2017). However, as notedestimated ratio reported above the Board approved the 2018 Plan prior to these changes in the law, and we are seeking stockholder approval of the Board-approved 2018 Plan. Therefore, the 2018 Plan includes several provisions that were intended to allow us to satisfy the requirements of "performance-based compensation" for purposes of Section 162(m) if we chose to structure awards under the 2018 Plan to so satisfy those requirements. Nothing in this proposal is intended to suggest that equity awards under the 2018 Plan granted with respect to taxable years beginning after December 31, 2017 will qualify for tax deductibility under Section 162(m) or will be structured in a manner that would have qualified for tax deductibility under Section 162(m) in the absence of the changes imposed by the Tax Cuts and Jobs Act. In addition, nothing in this proposal precludes us or the Compensation Committee from granting equity awards in respect of fiscal 2018 (i.e., our last tax year during which the exemption for "performance-based compensation" will be generally available) that do not qualify for tax deductibility under Section 162(m), including but not limited to time-based RSUs, nor is there any guarantee that equity awards intended to qualify for tax deductibility under Section 162(m) will ultimately be viewed as so qualifying by the Internal Revenue Service.

Eligible Persons

              Current employees, directors, consultants and advisors of us and our affiliates, and prospective employees, directors, consultant and advisors of us and our affiliates who have accepted offers of employment or consultancy from us or our affiliates will be eligible to participate in the 2018 Plan. As of January 12, 2018, this group includes eight non-employee directors and approximately 10,000 employees, consultants and advisors, including our executive officers.

Types of Awards

              The 2018 Plan authorizes the Compensation Committee to grant non-qualified and incentive stock options, SARs, restricted stock, restricted stock units (RSUs), stock bonus awards, dividend equivalents and performance compensation awards (including, but not limited to, performance stock units


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(PSUs). No grants of equity or cash awards are permitted under our 2015 Plan after March 8, 2018 if the 2018 Plan is approved by the stockholders.

Vesting and Exercise of Stock Options and SARs

              The exercise price of stock options and strike price of SARs granted under the 2018 Plan mayshould not be less than the fair market value of our common stock on the date of grant. The Compensation Committee determines fair market value using any permitted valuation method permitted under the stock rights exemption available under the IRS regulations pertaining to Section 409A of the Internal Revenue Code. The maximum exercise period may not be longer than ten (10) years, subject to equitable tolling as permitted under IRS regulations.

              The Compensation Committee determines when each stock option or SAR becomes exercisable, including the establishment of performance vesting criteria, if any. The award agreement specifies the consequences under the stock option or SAR of a recipient's termination of employment, serviceused as a director or other relationshipbasis for comparison between the participant and us or our affiliates.

Vesting of Awards Other than Stock Options and SARs

              The Compensation Committee may make the grant, issuance, retention or vesting of restricted stock, RSUs, stock bonus awards, dividend equivalents and performance compensation awards (including, but not limited to, PSUs) (collectively referred to herein as Full Value Awards) contingent upon continued employment with us, the passage of time, or performance vesting criteria (including the level of achievement against such performance vesting criteria it deems appropriate). Full Value Awards may, among other things, involve the transfer of actual shares, either at the time of grant or thereafter, or payment in cash or otherwise of amounts based on the value of shares of common stock. The Compensation Committee may, but is not required to, grant Full Value Awards in respect of fiscal 2018 under the 2018 Plan in a manner intended to qualify as "performance-based compensation" under Section 162(m) of the Code.

Vesting and Holding Limitations

              Awards vesting based on the passage of time will not vest more rapidly than pro-rata over a three-year period, and any award in respect of fiscal 2018 intended to qualify as "performance-based compensation" under Section 162(m) of the Code will have a performance period of at least twelve (12) months, unless the Compensation Committee or an individual award agreement provides otherwise in the case of death, disability, retirement or Change in Control. Notwithstanding the foregoing, upcompanies.

1 This exclusion amounted to 5% of the shares authorized on March 8, 2018 may be issued without these vesting limitations,global population. Countries from which all employees were excluded (and their respective head counts): Afghanistan (17), Bosnia and the limitations are not applicable to any awards to new hires, awards granted in substitutionHerzegovina (11), Brazil (439), Burkina Faso (2), Cambodia (95), Democratic Republic of equity awards issued by another entity, and non-employee directors.

              Until an executive officer's or non-employee director's stock ownership requirement is met, the executive officer or non-employee director must retain at least 75% of "gain shares" resulting from the exercise of a stock option or vesting of a performance compensation award (including, but not limited to, PSUs) or RSUs. With respect to stock options, "gain shares" means the total number of shares of common stock that are being exercised less the number of shares, if any, used in the case of a cashless exercise to pay for the exercise price. With respect to performance compensation awards (including, but not limited to, PSUs) and RSUs, "gain shares" means the total number of shares of common stock subject to any such equity award that vests. Gain shares do not include shares that are used to satisfy tax withholding obligations. See "Stock Ownership Guidelines" in theCompensation Discussion & Analysis section of this proxy statement for further information.


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Eligibility for Performance-Based Compensation Exemption under Section 162(m)

              As noted above, the Tax Cuts and Jobs Act eliminated the "performance-based compensation" exemption under Section 162(m)Congo (56), pursuant to which public companies could preserve the deductibility of compensation paid to certain executive officers in excess of $1 million that qualified as "performance-based compensation" under Section 162(m). This change in the law is effective with respect to taxable years beginning after December 31, 2017 (unless the compensation is provided pursuant to a written binding contract which was in effect on November 2, 2017, and which was not modified in any material respect on or after November 2, 2017). Accordingly, awards under the 2018 Plan with respect to taxable years beginning after December 31, 2017 will generally not be eligible for a "performance-based compensation" exemption under Section 162(m). Awards under the 2018 Plan with respect to taxable years beginning prior to December 31, 2017 may, but need not, include performance criteria that are intended to satisfy the "performance-based compensation" exemption under Section 162(m) of the Code. Performance-based awards that are payable in cash may also be granted under the 2018 Plan and subject to the maximum individual limits described above. To the extent that awards are intended to qualify as "performance-based compensation" under Section 162(m)Cote d’Ivoire (18), the performance criteria will be based on stock price appreciation (in the case of stock options or SARs) or on one or more of the following performance measures (in the case of Full Value Awards)Djibouti (17), each of which may be adjusted as provided in the 2018 Plan:

      net earnings or net income (before or after taxes); (ii) net income from operations; (iii) basic or diluted earnings per share (before or after taxes); (iv) net revenue or net revenue growth (in each case, whether or not net of subcontractor costs); (v) gross revenue or gross revenue growth (in each case, whether or not net of subcontractor costs); (vi) gross profit or gross profit growth; (vii) net interest margin; (viii) operating profit (before or after taxes); (ix) return measures (including, but not limited to, return on investment, assets, capital, employed capital, invested capital, equity or sales); (x) cash flow measures (including, but not limited to, operating cash flow, free cash flow or cash flow return on capital)El Salvador (2), which may but are not required to be measured on a per share basis; (xi) earnings before or after taxes, interest, depreciation and/or amortization (including EBIT and EBITDA); (xii) share price (including, but not limited to, growth measures or total stockholder return); (xiii) expense targets, cost reduction goals or general and administrative expense savings; (xiv) achieving specified improvements in collection of outstanding account receivable or specified reductions in write-offs; (xv) achieving a target days sales outstanding (DSO) level; (xvi) gross or net operating margins; (xvii) productivity ratios; (xviii) operating efficiency; (xix) measures of economic value added or other "value creation" metrics; (xx) enterprise value; (xxi) stockholder return; (xxii) client retention; (xxiii) employee retention); (xxiv) competitive market metrics; (xxv) objective measures of personal targets, goals, or completion of projects (including, but not limited to, succession and hiring projects, completion of specific acquisitions, reorganizations or other corporate transactions or capital-raising transactions, expansions of specific business operations or meeting business unit or project budgets); (xxvi) objective measures of customer satisfaction; (xxvii) working capital targets; (xxviii) asset growth; (xxix) dividend yield and dividend growth; (xxx) costs of capital, debt leverage, year-end cash position or book value; (xxxi) strategic objectives, including revenue and margin targets; or (xxxii) any combination of the foregoing.

              These performance measures may be applied individually or in any combination, either to us as a whole or to one or more of our affiliates, divisions, operational and/or business units, business segments, administrative departments, or any combination thereof, and measured either annually or cumulatively over a period of years, on an absolute, relative, or adjusted basis, relative to a pre-established target, to previous years' results, or to a designated comparison group, in each case as specified by the Compensation Committee in the award agreement.


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              The number of shares of common stock, stock options, cash or other benefits granted, issued, retainable or vested under an award that is intended to satisfy Section 162(m) upon satisfaction of performance criteria may be reduced by the Compensation Committee based on any further considerations that it may determine appropriate in its sole discretion. Specifically, the Compensation Committee is authorized to adjust or modify the calculation of a performance goal for a performance period within the time period permitted under Section 162(m) (typically within the first 90 days of a performance period) based on:

      asset write-downs; (ii) litigation or claim judgments or settlements; (iii) the effect of changes in tax laws, accounting principles, or other laws or regulatory rules affecting reported results; (iv) any reorganization and restructuring programs; (v) extraordinary nonrecurring items as described in Accounting Standards Codification Topic 225-20 (or any successor pronouncement thereto) and/or in management's discussion and analysis of financial condition and results of operations appearing in our annual report to stockholders for the applicable year; (vi) acquisitions or divestitures; (vii) any other specific unusual or nonrecurring events, or objectively determinable category thereof; (viii) foreign exchange gains and losses; (ix) discontinued operations and nonrecurring charges; and (x) a change in our fiscal year.

Administration

              The Compensation Committee administers the 2018 Plan, and has broad authority to do all things necessary or desirable, in its sole discretion, in connection with plan administration. The Compensation Committee will select who will receive awards; determine the type of awards and the number of shares covered thereby; determine fair market value; subject to the terms and limitations expressly set forth in the 2018 Plan, establish the terms, conditions and other provisions of the awards; determine whether, to what extent, and under what circumstances the awards may vest, be settled or exercised in cash, shares, other securities, other awards or other property, or be canceled, forfeited, or suspended and the method or methods by which awards may be settled, exercised, canceled, forfeited, or suspended; and determine whether, to what extent, and under what circumstances the delivery of cash, shares, other securities, other awards or other property and other amounts payable with respect to an award shall be deferred either automatically or at the election of the participant or of the Committee. The Compensation Committee may interpret the 2018 Plan and establish, amend and rescind any rules related to the 2018 Plan, and make remedial changes to the terms of an outstanding equity award to comply with applicable laws, regulations and listing requirements and to avoid unintended consequences resulting from unexpected events. The Compensation Committee may also accelerate the vesting or exercisability of, payment for, or lapse of restrictions on awards. The Compensation Committee has the discretion to permit the automatic exercise of vested in-the-money stock options and SARs, and may delegate this authority to our management. The Compensation Committee has the authority to toll the exercise period for options and SARs if such awards held by a former employee cannot be exercised due to trading or other legal restrictions.

              The Compensation Committee is also authorized to impose minimum amounts for partial exercises, to determine the fair market value of our stock from alternative valuation methods recognized by IRS regulations issued under Section 409A of the Code, and to establish special rules in order to comply with non-U.S. legal and tax law requirements with respect to grants of equity awards outside the United States.


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Amendments Requiring Stockholder Approval

              The Board may terminate, amend or suspend the 2018 Plan, provided that no action is taken by the Board (except those described under "Adjustments" below) without stockholder approval to:

      increase the number of shares that may be issued under the 2018 Plan;

      reprice, repurchase or exchange underwater stock options or SARs;

      cancel any stock option or SAR with an exercise price or strike price, as the case may be, above the current fair market value of our common stock;

      amend the maximum number of shares that be granted to a participant within a single calendar year;

      extend the term of the 2018 Plan;

      change the class of persons eligible to participate in the 2018 Plan; or

      otherwise implement any amendment required to be approved by stockholders to comply with applicable tax or regulatory requirements (including rules or requirements of any securities exchange on which our shares are listed or to prevent the company from being denied a tax deduction under Section 162(m) of the Internal Revenue Code).

Adjustments

              In the event of a stock dividend, extraordinary cash dividend or other distribution (whether in the form of securities or other property)Ethiopia (33), recapitalization, stock split, reverse stock split, reorganization, merger, consolidation, split-up, split-off, combination, reclassification, repurchase or exchange of shares or other securities of the company, issuance of warrants or other rights to acquire shares or other securities of the company, or other similar corporate transaction or event (including, without limitation, a change in control) that affects the shares, or unusual or nonrecurring events affecting the company, any of its affiliates, or the financial statements of the company or any of its affiliates, or changes in the applicable rules, rulings, regulations, or other requirements of any governmental body or securities exchange or inter-dealer quotation system, accounting principles or law, such that in either cash an adjustment is determined by the Compensation Committee in its sole discretion to be necessary or appropriate, then the Compensation Committee will make any such adjustments in such manner as it may deem equitable.

              The impact of the above events on our outstanding stock options, SARs and Full Value Awards granted under the 2018 Plan shall be determined in the Compensation Committee's sole discretion. Permitted adjustments include, but shall not be limited to, (i) adjusting the number of shares or other securities that may be delivered in respect of awards or with respect to which awards may be granted under the 2018 Plan, or the terms of any outstanding award, including, without limitation, the number of shares or other securities subject to such awards, the exercise price or strike price with respect to any award, or any applicable performance measures; (ii) subject to any limitations or reductions as may be necessary to comply with Section 409A of the Code and the regulations thereunder, providing for a substitution or assumption of awards, accelerating the exercisability of, lapse of restrictions on, or termination of, awards or providing for a period of time for exercise prior to the occurrence of such event; and (iii) subject to any limitations or reductions as may be necessary to comply with Section 409A of the Code and the regulations thereunder, cancelling any one or more outstanding awards and causing to be


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paid to the holders thereof, in cash, shares, other securities or other property, or any combination thereof, the value of such awards, if any, as determined by the Compensation Committee.

Clawback Requirements

              If the company is required to prepare an accounting restatement due to its material noncompliance with any financial reporting requirements under the securities laws, then each participant shall return to the company, or forfeit if not yet paid, the amount of any payment received with respect to an award under the 2018 Plan during the three-year period preceding the date on which the company is required to prepare the accounting restatement, based on the erroneous data, in excess of what would have been paid to the participant under the accounting restatement as determined by the Compensation Committee in accordance with Section 10D of the Securities Exchange Act of 1934, as amended, and any regulations promulgated, or national securities exchange listing conditions adopted, with respect thereto.

U.S. TAX CONSEQUENCES UNDER THE 2018 PLAN

              The following summary sets forth the tax events generally expected for United States citizens under current United States federal income tax laws in connection with equity awards under the 2018 Plan. This summary omits the tax laws of any municipality, state or foreign country in which a participant resides.

Stock Options

              A participant will realize no taxable income, and we will not be entitled to any related deduction, at the time a stock option that does not qualify as an "incentive stock option" under the Internal Revenue Code is granted under the 2018 Plan. At the time of exercise of such a non-qualified stock option, the participant will realize ordinary income, and we will be entitled to a deduction equal to the excess of the fair market value of the common stock on the date of exercise over the exercise price. Upon disposition of the shares, any additional gain or loss realized by the participant will be taxed as a capital gain or loss, long-term or short-term, based upon how long the shares are held.

              For stock options that qualify for treatment as "incentive stock options" under the Internal Revenue Code, a participant will realize no taxable income, and we will not be entitled to any related deduction, at the time an incentive stock option is granted under the 2018 Plan. If certain statutory employment and holding period conditions are satisfied before the participant disposes of shares acquired pursuant to the exercise of such an option, then no taxable income will result upon the exercise of such option, and we will not be entitled to any deduction in connection with such exercise. Upon disposition of the shares after expiration of the statutory holding periods, any gain or loss realized by a participant will be a long-term capital gain or loss. We will not be entitled to a deduction with respect to a disposition of the shares by a participant after the expiration of the statutory holding periods. Except in the event of death, if shares acquired by a participant upon the exercise of an incentive stock option are disposed of by such participant before the expiration of the statutory holding periods, such participant will be considered to have realized as compensation, taxable as ordinary income in the year of disposition, an amount, not exceeding the gain realized on such disposition, equal to the difference between the exercise price and the fair market value of the shares of common stock on the date of exercise of the option. We will be entitled to a deduction at the same time and in the same amount as the participant is deemed to have realized ordinary income. Any gain realized on the disposition in excess of the amount treated as compensation or any loss realized on the disposition will constitute capital gain or loss, respectively. Such capital gain or loss will be long-term or short-term based upon how long the shares were held. The foregoing discussion applies only for regular tax purposes. For alternative minimum tax purposes, an incentive stock option will be treated as if it were a non-qualified stock option.


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SARs; Performance Compensation Awards

              In general, (i) the participant will not realize income upon the grant of a SAR or performance compensation award; (ii) the participant will realize ordinary income, and we will be entitled to a corresponding deduction, in the year cash or shares of common stock are delivered to the participant upon exercise of a SAR or in payment of the performance compensation award; and the amount of such ordinary income and deduction will be the amount of cash received plus the fair market value of the shares of common stock received on the date of issuance. The federal income tax consequences of a disposition of unrestricted shares received by the participant upon exercise of a SAR or in payment of a performance compensation award are the same as described below with respect to a disposition of unrestricted shares.

Restricted and Unrestricted Stock; RSUs

              Unless the participant files an election to be taxed under Section 83(b) of the Internal Revenue Code: (i) the participant will not realize income upon the grant of restricted stock; (ii) the participant will realize ordinary income, and we will be entitled to a corresponding deduction (subject to the limitations of Section 162(m) of the Internal Revenue Code)Ghana (46), for grants of restricted stock subject only to time-based vesting and not including any performance conditions, when the restrictions have been removed or expire; and (iii) the amount of such ordinary income and deduction will be the fair market value of the restricted stock on the date the restrictions are removed or expire. If the participant files an election to be taxed under Section 83(b) of the Internal Revenue Code, the tax consequences to the participant will be determined as of the date of the grant of the restricted stock rather than as of the date of the removal or expiration of the restrictions.

              A participant will not realize income upon the grant of RSUs, but will realize ordinary income, and we will be entitled to a corresponding deduction (subject to the limitations of Section 162(m) of the Internal Revenue Code)Lebanon (10), for grants of RSUs subject only to time-based vesting and not including any performance conditions, when the RSUs have vested and been settled in cash and/or shares of common stock. The amount of such ordinary income and deduction will be the amount of cash received plus the fair market value of the shares of common stock received on the date of issuance.

              When the participant disposes of restricted or unrestricted stock, the difference between the amounts received upon such disposition and the fair market value of such shares on the date the participant realizes ordinary income will be treated as a capital gain or loss, long-term or short-term, based upon how long the shares are held.

Section 409A

              Section 409A of the Internal Revenue Code provides additional tax rules governing non-qualified deferred compensation. Generally, Section 409A will not apply to awards granted under the 2018 Plan, but may apply in some cases to RSUs, share-denominated performance compensation awards and other Full Value Awards. For such awards subject to Section 409A, certain of our officers may experience a delay of up to six months in the settlement of the awards in shares of our stock.

Withholding

              The 2018 Plan permits us to withhold from awards an amount sufficient to cover any required withholding taxes. In lieu of cash, the Compensation Committee may permit a participant to cover withholding obligations through a reduction in the number of shares to be delivered to such participant or by delivery of shares already owned by such participant.

Liberia (6), Madagascar (30), Malawi (80), Senegal (4), South Sudan (14), Sri Lanka (37), Tajikistan (5), Timor-Leste (1), Tonga (4), Zambia (59)


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Section 162(m)

              As described above, cash and equity awards granted under the 2018 Plan may be structured to qualify as "performance-based compensation" under Section 162(m) of the Internal Revenue Code, but only with respect to taxable years beginning prior to December 31, 2017. Pursuant to the Tax Cuts and Jobs Act, the "performance-based compensation" exemption will no longer be available with respect to taxable years beginning after December 31, 2017 (unless the compensation at issue is provided pursuant to a written binding contract which was in effect on November 2, 2017, and which was not modified in any material respect on or after November 2, 2017). To qualify for the "performance-based compensation" exemption during the period such exemption is available, the 2018 Plan must satisfy the conditions set forth in Section 162(m) of the Internal Revenue Code, and stock options and other awards must be granted under the 2018 Plan by a committee consisting solely of two or more outside directors (as defined under Section 162(m) regulations) and must satisfy the 2018 Plan's limit on the total number of shares that may be awarded to any one participant during any calendar year (or, for awards denominated in shares but paid in cash, other securities, other awards or other property, no more than the fair market value of that limit on the last day of the performance period to which the award relates). For awards other than stock options and SARs to qualify, the grant, issuance, vesting, or retention of the award must be contingent upon satisfying one or more of the performance criteria set forth in the 2018 Plan, as established and certified by a committee consisting solely of two or more outside directors. The rules and regulations promulgated under Section 162(m) of the Internal Revenue Code are complicated and subject to change from time to time, and may apply with retroactive effect. In addition, a number of requirements must be met in order for particular compensation to so qualify. As such, there can be no assurance that any compensation awarded or paid under the 2018 Plan will be deductible under all circumstances.

KEY METRICS RELATED TO THE EXISTING PLAN

              The "burn rate" measures how quickly a company uses shares under an equity plan. Our burn rate is calculated by dividing the number of outstanding equity awards granted during the year by the weighted average number of shares of common stock outstanding during the year. A higher burn rate indicates an increased number of equity awards being granted to employees and/or directors. The following table sets forth our burn rate for fiscal years 2015, 2016 and 2017 under our equity plans:

Tetra Tech 2024 Proxy Statement 70

Item 3: Ratification of Appointment of Independent Registered Public Accounting Firm
 
 2015 2016 2017 Average 

Number of equity awards granted

  640,052  610,180  522,516   

Burn rate %

  1.1%  1.0%  0.9%  1.0% 

              "Overhang" provides a measure

Item 3: Ratification of the potential dilutive effectAppointment of outstanding equity awards and shares available for future grants under equity plans. Our overhang is calculated by dividing the number of shares of common stock subject to equity awards outstanding plus the number of shares of common stock available to be granted (the sum of these numbers is referred to as the numerator), by the total number of common shares outstanding plus the numerator. Our overhang at October 1, 2017 was 8.6%, calculated based on a total of 2,639,072 shares of our common stock subject to equity awards outstanding under our equity plans, 2,644,111 shares available for new award grants under the 2015 Plan and 55,872,960 shares of our common stock issued and outstanding as of such date. Assuming the 2018 Plan and the 3,000,000 shares proposed to be authorized for grant thereunder are approved, our overhang would have been 9.2% as of such date (excluding the shares available for grant under the 2015 Plan as of such date which will no longer be available if the 2018 Plan is approved).


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NEW PLAN BENEFITS

              The benefits that will be awarded or paid in the future under the 2018 Plan cannot currently be determined. Awards granted under the 2018 Plan are within the discretion of the Compensation Committee, subject to limits on the maximum amounts that may be awarded to any individual. As of January 12, 2018, the closing price of a share of our stock was $49.20.

RECOMMENDATION OF THE BOARD OF DIRECTORS

Your Board of Directors recommends that stockholders vote FOR approval of the Tetra Tech, Inc. 2018 Equity Incentive Plan. Properly dated and signed proxies will be so voted unless stockholders specify otherwise.


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Independent Registered Public Accounting Firm
ITEM 4 – RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee has appointed PricewaterhouseCoopers LLP (PwC)PwC as our independent registered public accounting firm for the 20182024 fiscal year, and our Board is seeking stockholder ratification of the appointment. Stockholder ratification is not required by our bylaws or applicable laws and regulations. However, ourOur Board, however, annually submits the appointment for stockholder ratification as a matter of good corporate governance. If stockholders were not to ratify the appointment, the Audit Committee would reconsider whether or not to retain PwC, but could determine to do so inat the Committee'sAudit Committee’s discretion. In addition, even if the appointment is ratified, the Audit Committee could subsequently appoint a different independent registered public accounting firm without stockholder approval if the Committee werewas to determine that doing soaction would be in the best interests of our company and stockholders.

PwC has been our independent registered public accounting firm since fiscal yearFY 2004 and served in that capacity for the 20172023 fiscal year. PwC is knowledgeable about our operations and accounting practices and we believe that PwC is well qualified to act as our independent registered public accounting firm. Some governance stakeholders have suggested that a long-tenured auditor poses an independence risk. The Audit Committee, however, has several practices in place that mitigate this potential risk, including the following:


Review of all non-audit services and engagements provided by PwC in annually assessing PwC's independence;

PwC’s independence

Periodic consideration of whether to change the independent registered public accounting firm based on its assessment of PwC'sPwC’s audit quality, performance, compensation, and independence;

independence

Regular meetings with PwC without management present and with management without PwC present; and

present

Involvement in the interview and selection process for any new lead audit partner.

partner

In order to regularly bring a fresh perspective to the audit engagement, a new lead audit partner is designated at least every five years, and a new partner was so designated at the beginning of fiscal 2015.years. The Audit Committee Chair interviewed the partner prior to histhis designation, and the Audit Committee as a whole was directly involved with members of senior management and PwC in making the selection.

In determining whether to reappoint PwC, the Audit Committee considered the qualifications, performance, and independence of the firm and the audit engagement team,team; the quality of its discussion with PwC,PwC; and the fees charged by PwC for the level and quality of services provided. Although no formal statement from PwC is planned, representatives of the firm will be given the opportunity to make a statement if they so desire and will be present at the 2024 Annual Meeting to answer appropriate questions from stockholders.

RECOMMENDATION OF THE BOARD OF DIRECTORS

Your

Vote Required
Approval of this advisory vote requires the affirmative vote of a majority of shares of common stock present or represented and entitled to vote on the proposal at the 2024 Annual Meeting. Abstentions will have the same effect as a vote “AGAINST” the proposal. Broker non-votes will have no effect on the outcome of the advisory vote.
Recommendation of Board of Directors
Our Board of Directors recommends that you vote FOR ratification of the appointment of PwC as ourTetra Tech’s independent registered public accounting firm for the 20182024 fiscal year.year. Properly dated and signed proxies will be so voted unless stockholders specify otherwise.


Auditor Independence

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AUDITOR INDEPENDENCE

              We have been advised by PwC that neither the firm nor any member thereof has any financial interest, direct or indirect, in any capacity in our company or its subsidiaries. As a result,

PwC has confirmed that it is in compliance with all rules, standards, and policies of the Public Company Accounting Oversight Board (PCAOB) and the regulations of the SEC governing auditor independence. The Audit Committee considers at least annually whether PwC'sPwC’s provision of non-audit services is compatible with maintaining auditor independence.

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Tetra Tech 2024 Proxy Statement 71

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Item 3: Ratification of Appointment of Independent Registered Public Accounting Firm
Auditor Fees
The following is a summary of the fees PwC has billed or expected to be billed to us by PwCTetra Tech for professional services rendered for the fiscal years ended October 1, 20172023, and October 2, 2016:

2022. The increase in fees for FY 2023 primarily was due to additional work associated with the acquisition and integration of RPS Group.
Fee CategoryFY 2023 FeesFY 2022 Fees
Audit Fees$4,619,243$3,513,130
Audit-Related Fees130,00033,418
Tax Fees264,114161,467
All Other Fees4,1505,400
Total Fees$5,017,508$3,713,415
Audit Fees

                Fee Category 



Fiscal 2017 Fees 

Fiscal 2016 Fees  

Audit Fees

 $2,826,409 $2,701,250 

Audit-Related Fees

    11,189 

Tax Fees

  170,444  354,644 

All Other Fees

  3,600  3,600 

Total Fees

 $3,000,453 $3,070,683 

              Audit Fees.    Consists ofThese fees are billed for professional services rendered for the integrated audit of our consolidated financial statements and our internal control over financial reporting, for the reviews of the interim consolidated financial statements included in our quarterly reports, and for services that are normally provided by PwC in connection with statutory and regulatory filings or other engagements.

Audit-Related Fees.    Consists ofFees
These fees are billed for opinion on controls forassurance and related services that were related to the Quebec autorité des marches (AMF) certification.

performance of the audit or review of our financial statements and were not reported under “Audit Fees.” This category may include fees related to the performance of audits and attestation services not required by statute or regulations, due diligence activities related to acquisitions, and accounting consultations about the application of generally accepted accounting principles to proposed transactions.

Tax Fees.    Consists ofFees
These fees are billed for professional services for tax compliance, tax advice, tax planning, and tax returns. These services include assistance regarding federal, state, and international tax compliance; assistance with tax reporting requirements, tax returns, and audit compliance; mergers and acquisitionsM&A tax compliance; and tax advice on international and state tax matters. None of these services werewas provided under contingent fee arrangements.

All Other Fees.Fees
These fees wereare associated with an annual license feefees for software used by management in performing technical research.

POLICY ON AUDIT COMMITTEE PRE-APPROVAL OF AUDIT AND PERMISSIBLE NON-AUDIT SERVICES

research and ensuring completeness of financial statement disclosures.

Policy on Audit Committee Pre-Approval of Audit and Permissible Non-Audit Services
The Audit Committee'sCommittee’s policy is to pre-approve all audit and permissible non-auditnon audit services to be provided by the independent registered public accounting firm, subject to limited discretionary authority granted to our executive management. These services may include audit services, audit-relatedaudit related services, tax services, and other services. Pre-approval is detailed as to the particular service or category of services and is generally subject to a specific budget.services. The independent registered public accounting firm and management are required to periodically report to the Audit Committee regardingon the extent of services provided by the independent registered public accounting firm in accordance with this pre-approval and the fees for the services performed to date. The Audit Committee may also pre-approve particularspecific services on a case-by-case basis.


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The Audit Committee pre-approved all audit and permissible non audit services provided by PwC in FY 2022 and FY 2023 in accordance with this policy.
AUDIT COMMITTEE REPORT

Tetra Tech 2024 Proxy Statement 72

Audit Committee Report
Audit Committee Report
Management is responsible for the Company'sTetra Tech’s internal controls and the financial reporting process. The Company'sCompany’s independent registered public accounting firm is responsible for performing an independent audit of the Company'sCompany’s consolidated financial statements and internal controls over financial reporting in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB)PCAOB and to issue a report thereon. The Audit Committee'sCommittee’s responsibility is to monitor and oversee these processes, but the Audit Committee is not responsible for preparing the Company'sCompany’s financial statements or auditing those financial statements, which are the responsibilities of management and the independent auditors, respectively.

The Audit Committee has reviewed with PricewaterhouseCoopers LLP (PwC)PwC the matters that are required to be discussed with the Audit Committee under generally accepted auditing standards.the applicable requirements of the PCAOB and the SEC. The Audit Committee has also discussed with the Company'sCompany’s management auditors and PwC the overall scope and plan for their respective audits. The Audit Committee meets regularly with the management auditors and independent auditors to discuss the results of their examinations, their evaluations of the Company'sCompany’s internal controls, and the overall quality of the Company'sCompany’s financial reporting.

              In the context of the foregoing, the

The Audit Committee has reviewed and discussed with management the audited financial statements of the Company for the fiscal year ended October 1, 2017 with management.2023. In connection with that review, management represented to the Audit Committee that the Company'sCompany’s consolidated financial statements were prepared in accordance with generally accepted accounting principles. The Audit Committee has also reviewed management'smanagement’s report on its assessment of internal controls over financial reporting, as required under the Sarbanes-OxleySarbanes Oxley Act of 2002. In its report, management provided a positive assertion that internal controls over financial reporting were in place and operating effectively as of October 1, 2017.

2023.

The Audit Committee has discussed with PwC the consolidated financial statements with PwC and it has also discussed with PwCas well as the matters required to be discussed pursuant to Auditing Standard No. 16,1301, Communications with Audit Committees. The Audit Committee has also received a letter from PwC regarding its independence from the Company as required by PCAOB Ethics and Independence Rule 3526, (CommunicationCommunication with Audit Committees Concerning Independence),Independence, has discussed with PwC the independence of the firm, and has considered all of the above communications as well as all audit, audit-relatedaudit related, and non-audit services provided by PwC. InWith reliance upon the foregoing, the Audit Committee has determined that PwC is an independent registered public accounting firm with respect to the Company within the meaning of the Securities Act of 1933, as amended, and the regulations thereunder adopted by the Securities and Exchange CommissionSEC and the PCAOB.

Based on the reviews and discussions referred todetailed above, the Audit Committee recommended to the Board of Directors that the audited financial statements be included in the Company'sCompany’s Annual Report on Form 10-K for the fiscal year endedFYE October 1, 2017,2023, as filed with the Securities and Exchange Commission.

Hugh M. Grant,SEC.

Respectfully submitted by:
Gary R. Birkenbeuel, Chair
J. Christopher Lewis

Kimberly E. Ritrievi

Kirsten M. Volpi

This Audit Committee Report does not constitute soliciting material and should not be deemed filed or incorporated by reference into any of our filings under the Securities Act of 1933, as amended, or the Securities Exchange Act, of 1934, as amended, whether made before or after the date hereof,of this proxy statement, unless specifically incorporated by reference herein.



Tetra Tech 2024 Proxy Statement 73

Security Ownership Information
Security Ownership Information
Security Ownership of Contents

Management and Significant Stockholders
SECURITY OWNERSHIP INFORMATION

INSIDER TRADING POLICY; PROHIBITION ON HEDGING AND PLEDGING

              Our insider trading policy prohibits our directors, officers and employees from engaging in transactions in our company's stock while in the possession of material non-public information and disclosing material non-public information to unauthorized persons, outside our company. In addition, this policy restricts trading for directors and officers (including all NEOs) during blackout periods, which generally begin two weeks before the end of each fiscal quarter and end two business days after the release of earnings for the quarter.

              Our insider trading policy expressly prohibits our directors, officers and employees from (i) engaging in hedging or monetization transactions such as zero-cost collars and forward sale contracts designed to hedge or offset any decrease in the market value of shares of our common stock held by them, or (ii) pledging any of their shares of our common stock to secure personal loans or other obligations, including by holding such shares in a margin account. To our knowledge, none of our directors or executive officers has hedged or pledged our common stock.

SECURITY OWNERSHIP OF MANAGEMENT AND SIGNIFICANT STOCKHOLDERS

The following table sets forth information known to usTetra Tech with respect to beneficial ownership of our common stock at December 1, 2017January 2, 2024, by:

all
All those persons known by us to own beneficially more than 5% or more of our common stock;

stock
each
Each director and nominee;

director nominee
our NEOs; and


Our NEOs
all
All directors and executive officers as a group.

group

Beneficial ownership is determined under the rules of the SEC and generally includes voting or investment power with respect to securities. ExceptTo our knowledge, except as indicated in the footnotes to this table and pursuant to applicable community property laws, to our knowledge the persons named in the table below have sole voting and investment power with respect to all shares of common stock beneficially owned. The number of shares beneficially owned by each person or group as of December 1, 2017January 2, 2024, includes shares of common stock that such person or group had the right to acquire on or within 60 days after December 1, 2017,January 2, 2024, including, but not limited to, upon the exercise of options. References to options in the footnotes of the table below include only options to purchase shares that were exercisable on or within 60 days after December 1, 2017. For each individual and group included in the table below,January 2, 2024. Unless otherwise indicated, percentage ownership is calculated by dividing the number of shares beneficially owned by such person or group by the sum of (1) the 55,895,08953,465,783 shares of common stock outstanding on December 1, 2017 plus the number ofJanuary 2, 2024, and (2) any shares of common stock that such person or group hadhas the right to acquire on or within 60 days after December January 2, 2024.
Beneficial Ownership of Common Stock
Name of Beneficial Owner1
Shares
Beneficially
Owned (#)
Percentage
Owned
BlackRock, Inc.2
5,730,20810.8
The Vanguard Group, Inc.3
5,336,90110.1
Pictet Asset Management SA4
2,722,3975.1
AllianceBernstein L.P.5
2,955,5355.6
Roger R. Argus2,154*
Dan L. Batrack48,601*
Gary R. Birkenbeuel6
7,780*
Steven M. Burdick48,631*
Prashant Gandhi737*
Preston Hopson13,742*
Joanne M. Maguire7
32,394*
Christiana Obiaya*
Kimberly E. Ritrievi29,940*
Leslie L. Shoemaker8
86,048*
J. Kenneth Thompson9
22,885*
Kirsten M. Volpi10
16,348*
All directors and executive officers as a group (14 persons)11
325,729*
* Less than 1%.
1 2017. Unless otherwise stated,indicated, the business address of each of our directors, nominees and executive officers listedperson in thethis table below is c/o Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107.


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91107, Attention: Corporate Secretary.

Name of Beneficial Owner






Number of
Shares
Beneficially
Owned




Percentage
Owned
​ ​ 

BlackRock, Inc.(1)

  7,446,086 13.3

The Vanguard Group, Inc.(2)

  4,910,049 8.8

Dimensional Fund Advisors LP(3)

  3,242,303 5.8

Dan L. Batrack(4)

  576,914 *

Steven M. Burdick(5)

  147,921 *

Ronald J. Chu(6)

  77,803 *

Hugh M. Grant(7)

  77,721 *

Patrick C. Haden(8)

  42,181 *

J. Christopher Lewis(9)

  108,489 *

Joanne M. Maguire(10)

  13,100 *

Kimberly E. Ritrievi(11)

  37,421 *

Janis B. Salin(12)

  94,177 *

Leslie L. Shoemaker(13)

  123,856 *

Albert E. Smith(14)

  68,378 *

J. Kenneth Thompson(15)

  70,396 *

Kirsten M. Volpi(16)

  34,421 *

All directors and executive officers as a group (23 persons)(17)

  1,915,456 3.4

*
Less than 1%
(1)
2All information regarding share ownership is taken from and furnished in reliance upon the Schedule 13G (Amendment No. 8)12), dated as of January 11, 2017,December 31, 2022, filed by BlackRock, Inc., with the SEC on February 7, 2023, whose address is 55 East 52nd Street, New York, NYNew York 10055.
(2)
According to the Schedule 13G/A, BlackRock, Inc. has sole voting power over 5,477,0456 shares of our common stock and sole dispositive power over 5,730,208 shares of our common stock.

Tetra Tech 2024 Proxy Statement 74

Security Ownership Information
3All information regarding share ownership is taken from and furnished in reliance upon the Schedule 13G (Amendment No. 5)12), dated as of February 9, 2017,December 30, 2022, filed by The Vanguard Group, Inc., (Vanguard) with the SEC on February 9, 2023, whose address is 100 Vanguard Boulevard, Malvern, PAPennsylvania 19355.
(3)
According to the Schedule 13G/A, Vanguard has shared voting power over 20,402 shares of our common stock, sole dispositive power over 5,269,628 shares of our common stock, and shared dispositive power over 67,273 shares of our common stock.
4All information regarding share ownership is taken from and furnished in reliance upon the Schedule 13G, dated as of February 9, 2017,December 31, 2022, filed by Dimensional Fund Advisors LP,Pictet Asset Management SA (Pictet) with the SEC on February 3, 2023, whose address is Building One, 6300 Bee Cave Road, Austin, TX 78746.
(4)
60 Route de Acacias, 1211 Geneva 73, Switzerland. According to the Schedule 13G, Pictet has sole voting power over 2,722,397 shares of our common stock and sole dispositive power over 2,773,397 shares of our common stock.
5 All information regarding share ownership is taken from and furnished in reliance upon the Schedule 13G, as of December 31, 2022, filed by AllianceBernstein L.P. with the SEC on February 14, 2023, whose address is 1345 Avenue of the Americas, New York, NY 10105. According to the Schedule 13G, AllianceBernstein has sole voting power over 2,249,023 shares of our common stock, sole dispositive power over 2,893,389 shares of our common stock and shared dispositive power over 62,146 shares of our common stock.
6Includes options to purchase 355,078 shares.
(5)
243 shares that are exercisable on or within 60 days after January 2, 2024.
7Includes options to purchase 107,234 shares.
(6)
16,400 shares that are exercisable on or within 60 days after January 2, 2024.
8Includes options to purchase 47,180 shares.
(7)
11,161 shares that are exercisable on or within 60 days after January 2, 2024.
9Includes options to purchase 61,000 shares.
(8)
8,400 shares that are exercisable on or within 60 days after January 2, 2024.
10Includes options to purchase 29,000 shares.
(9)
4,000 shares that are exercisable on or within 60 days after January 2, 2024.
11Includes options to purchase 61,000 shares. The business address of Mr. Lewis is c/o Riordan, Lewis & Haden, 10900 Wilshire Boulevard, Suite 850, Los Angeles, CA 90024.
(10)
Includes options to purchase 12,200 shares.
(11)
Includes options to purchase 24,800 shares. The business address of Dr. Ritrievi is 1850 Brightwaters Blvd. NE, Saint Petersburg, FL 33704.
(12)
Includes options to purchase 73,326 shares.
(13)
Includes options to purchase 75,543 shares.
(14)
Includes options to purchase 29,000 shares.
(15)
Includes options to purchase 53,000 shares. The business address of Mr. Thompson is 1120 Huffman Rd., Suite 24 PMB203, Anchorage, AK 99515.
(16)
Includes options to purchase 24,800 shares. The business address of Ms. Volpi is c/o Colorado School of Mines, 1500 Illinois St., Golden, CO 80401.
(17)
Includes options to purchase 1,222,694 shares.
45,784 shares that are exercisable on or within 60 days after January 2, 2024.

SECTION

Section 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Beneficial Ownership Reporting Compliance

Section 16(a) of the Securities Exchange Act of 1934, as amended, requires our executive officers, directors, and owners of more than 10% of our equity securities (collectively, our insiders), to timely file initial reports of ownership and reports of changes in ownership with the SEC. Due to the complexity of SEC reporting rules, we undertake to file these reports on behalf of our directors and executive officers and have instituted procedures to assist them with complying with their reporting obligations. To our knowledge, based solely on our review of SEC filings, our records, and written


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representations from certain of our insiders that no other reports were required to have been filed, we believe that all of our insiders timely complied with the Section 16(a) filing requirements applicable to them on a timely basis during fiscal 2017.

RELATED PERSON TRANSACTIONS

FY 2023.

Related Person Transactions
Our Board of Directors has adopted a written related person transactions policy. Under the policy, the Audit Committee (or other committee designated by the NCG Committee) reviews transactions between usTetra Tech and "related persons."related persons, including to identify, review, approve and disclose, if necessary, any transaction, arrangement or relationship (or any series of similar transactions, arrangements or relationships) in which (i) we (including any of our subsidiaries) was, is or will be a participant; (ii) the amount involved exceeds $120,000; and (iii) a related person had, has or will have a direct or indirect material interest (a “Related Person Transaction”). For purposes of the policy, a related person“related person” is a director, executive officer, nominee for director, or a greaterbeneficial owner of more than 5% beneficial owner of our common stock, in each case, since the beginning of the last fiscal year, and their immediate family members.

              The policy provides that, barring special facts or circumstances, a related person does not have a direct or indirect material interest in the following categories of transactions:

      employment-related compensation to executive officers that is determined by the Compensation Committee;

      compensation to non-employee directors that is reported in our proxy statement;

      transactions with another company at which:

      the related person's only relationship is as a beneficial owner of less than 10% of that company's shares or as a limited partner holding interests of less than 10% in such partnership; or

      the related person is the beneficial owner of less than a majority interest in that company if the related person is solely related to us because of his or her beneficial ownership of greater than 5% of our common stock;

      transactions where the related person's interest arises solely from the ownership of publicly traded securities issued by us and all holders of such securities receive proportional benefits;

      transactions involving services as a bank depositary of funds, transfer agent, registrar, trustee under a trust indenture, or similar services;

      transactions where the rates or charges involved are determined by competitive bids;

      transactions involving the rendering of services as a common or contract carrier, or public utility, at rates or charges fixed in conformity with law or governmental authority;

      ordinary course of business travel and expenses, advances and reimbursements; and

      payments made pursuant to (i) directors' and officers' insurances policies; (ii) our certificate of incorporation or bylaws; and/or (iii) any policy, agreement or instrument previously approved by our Board of Directors, such as indemnification agreements.

Related person transactionsPerson Transactions that do not fall into onecertain pre-approved categories in accordance with Item 404 of Regulation S-K promulgated under the above categoriesExchange Act must be reviewed by our Disclosure Committee, which consists of an internal team of senior representatives from our finance, accounting, legal, human resources, tax, treasury, investor relations, and information technology departments. The Disclosure Committee determines whether a related person could have a significant


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interest in such athe transaction, and, any suchif so, the transaction is referred to the Audit Committee (or other designated committee). Transactions also may also be identified through our Code of Business Conduct, our quarterly certification process, or our other policies and procedures and reported to the Audit Committee (or other designated committee). The DisclosureAudit Committee will review the material facts of all related person transactionsRelated Person Transactions and either approve, ratify, rescind, or take other appropriate action (in its discretion) with respect to the transaction.

              We did not have any related person transactions

Tetra Tech had no Related Person Transactions in fiscal 2017.


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FY 2023.
MEETING AND VOTING INFORMATION

Tetra Tech 2024 Proxy Statement 75

Meeting and Voting Information
Meeting and Voting Information
This proxy statement is being furnished to stockholders on behalf of our Board to solicit proxies for the 2024 Annual Meeting to be held on Thursday, March 8, 2018,February 29, 2024, at 10:00 a.m. Pacific Time, at the Westin Pasadena, 191 N.North Los Robles Avenue, Pasadena, California 91101, and at any adjournment or postponement thereof. The items of business to be acted upon at the meeting are set forth in the Notice of 2024 Annual Meeting of Stockholders appearing at the beginning of this proxy statement.

              All stockholders are urged to vote by telephone or

Delivery of Annual Report on the internet by following the instructions on the Notice of Internet Availability of Proxy Materials (Notice). If you have properly requested and received a paper copy of this proxy statement, you may vote your shares by (a) submitting a proxy by telephone or on the internet by following the instructions on the proxy card or (b) completing, dating and signing the proxy card and promptly returning it in the pre-addressed, postage-paid envelope provided. Stockholders of record may obtain a copy of this proxy statement without charge by writing to our Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107.

DELIVERY OF ANNUAL REPORT ON FORMForm 10-K

We will mail without charge, upon written request, a copy of our Annual Report on Form 10-K for the fiscal year endedFYE October 1, 2017,2023, including the consolidated financial statements, schedules and list of exhibits, and any particular exhibit specifically requested. Requests should be sent to our Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107. Our Annual Report on Form 10-K is also available atwww.tetratech.com.

DELIVERY OF PROXY MATERIALS

tetratech.com.

Delivery of Proxy Materials
We have elected to provide access to our proxy materials on the Internet.internet. Accordingly, we are sending the Notice of 2024 Annual Meeting of Stockholders (“Notice”) to our stockholders of record. Brokers, banks, and other nominees (collectively, nominees) who hold shares on behalf of the beneficial owners (also called street“street name holders)holders”) will send a similar notice.notice to beneficial owners. All stockholders will have the ability to access our proxy materials on the website referred to in the Notice.Notice or to request a printed copy of the proxy materials. Instructions on how to request printed proxy materials by mail, including an option to receive paper copies in the future, may be foundare provided in the Notice and on the website referred to in the Notice.

              On or before January 26, 2018, we intend to make this proxy statement available on the Internet and mail the Notice to all stockholders entitled to vote at the Annual Meeting.

We intend to mail this proxy statement, together with a proxy card, to stockholders entitled to vote at the 2024 Annual Meeting who properly request paper copies of these materials within three business days of request. If you hold your shares in street name, you may request paper copies of the proxy statement and proxy card from your nominee by following the instructions on the notice your nominee provides to you.

HOUSEHOLDING

Householding
We have adopted a procedure approved by the SEC called householding.“householding.” Under this procedure, we are permitted to deliver a single copy of our proxy materials, including this proxy statement and annual reportour Annual Report, to stockholders sharing the same address.address who did not receive the Notice and who did not otherwise notify us of their desire to receive multiple copies of our proxy materials. Householding allows us to reduce our printing and postage costs and limits the volume of duplicative information received at your household. Householding affects only the delivery of proxy materials; it has no impact on the delivery of dividend checks.

              For certain holders who share

We will promptly deliver, upon oral or written request, a singleseparate copy of the proxy materials to any stockholder residing at an address we are sendingto which only one annual report and proxy statement to that address unless we received instructions to the contrary from any stockholder at that


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address.copy was mailed. If you wish to receive an additional copy of our annual report or proxy statement,materials, or if you received multiple copies of our annual report or proxy statementmaterials and wish to receive a single copyrequest householding in the future, you may make such request by writing to our Corporate Secretary at Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107.

If you are a street name holder and wish to revoke your consent to householding and receive separate copies of our proxy statement and annual reportmaterials in future years, you may call Broadridge Investor Communications ServicesSolutions, Inc. toll-free at (800) 542-1061 or write to them c/o Householding Department, 51 Mercedes Way, Edgewood, New York 11717.

SHARES ENTITLED TO VOTE

Shares Entitled to Vote
Stockholders of record as of the close of business on January 12, 20182, 2024, are entitled to notice of, and to vote at, the 2024 Annual Meeting. Our only class of shares outstanding is common stock, and there were 55,930,66553,465,783 shares of our common stock outstanding on January 12, 2018. A2, 2024. Pursuant to our bylaws, a list of stockholders entitled to vote will be available for inspection at least 10 days before the 2024 Annual Meeting and at the 2024 Annual Meeting. Each stockholder of record is entitled to one vote for each share of common stock held on the record date.


Tetra Tech 2024 Proxy Statement 76

TABLE OF CONTENTS VOTING YOUR SHARES

Meeting and Voting Information
Voting Your Shares
Voting in Person
You may vote by attending the 2024 Annual Meeting and voting in person or you may vote by submitting a proxy. If you hold your shares in street name, you may only vote in person at the meeting only if you properly request and receive a legal proxy in your name from the nominee that holds your shares.

              The See Shares Registered in Street Name below.

If you hold your shares of common stock as a record holder (i.e., directly in your name), your method of voting by proxy differs depending on whether you are viewing this proxy statement on the Internetinternet or reviewing a paper copy, as follows:

if
If you are viewing this proxy statement on the Internet,received a notice of internet availability or an email, you may vote your shares by (i)(1) submitting a proxy on the Internetinternet by following the instructions on the website or (ii)(2) requesting a paper copy of the proxy materials and following one of the methods described below; and

below.
if
If you are reviewingreceived a paper copy of this proxy statement,card or voting instruction card, you may vote your shares by (i)(1) submitting a proxy by telephone or on the Internetinternet by following the instructions on the proxy card or (ii)(2) completing, dating, and signing the proxy card included with the proxy statement and returning it in the pre-addressed, postage-paid envelope provided.

We encourage you to vote by telephone or on the Internetinternet since thesethose methods immediately record your votesvote and allow you to confirm that your votes havevote has been properly recorded.

If you vote by internet or telephone, then you need not return a written proxy card by mail.

Shares Registered in Street Name
If you hold your shares of common stock in street name, which means your shares are held of record by a nominee, you will receive instructions from your nominee on how to vote your shares. Your nominee will allow you to deliver your voting instructions over the internet and might also permit you to vote by telephone. In addition, if you received a printed copy of this proxy statement, you may submit your voting instructions by completing, dating, and signing the voting instruction form included with the proxy statement and promptly returning it in the pre-addressed, postage-paid envelope provided. If you vote by internet or telephone, then you need not return a written voting instruction form by mail.
Manner of Voting in the Absence of Instructions
In the event that you return a signed and valid proxy card on which no directions are specified, your shares will be voted

      in the following manner:

FOR the election of the nineseven directors nominated by our Board to serve a one-year term;

terms until the 2025 Annual Meeting, and until their respective successors are duly elected and qualified or until his or her resignation or removal.

FOR the approval, on an advisory basis, of our named executive compensation;

officers’ compensation.

FOR the approval of the 2018 Equity Incentive Plan;

FOR the ratification of the appointment of PricewaterhouseCoopers LLPPwC as our independent registered public accounting firm for fiscal year 2018; and
FY 2024.

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      in
In the discretion of the proxy holders as to any other matters that may properly come before the 2024 Annual Meeting or any postponement or adjournment of the 2024 Annual Meeting.

REVOKING YOUR PROXY OR CHANGING YOUR VOTE

Deadline for Voting By Proxy
If you are a stockholder of record, your proxy must be received by telephone or via the internet by 11:59 p.m. Eastern Time on February 28, 2024, for your shares to be voted at the 2024 Annual Meeting. If you are a stockholder of record and you received a printed set of proxy materials, you also have the option of completing, signing, dating, and returning the proxy card enclosed with the proxy materials before the 2024 Annual Meeting for your shares to be voted at the meeting. If you hold your shares of common stock in street name, please comply with the deadlines included in the voting instructions provided by the nominee that holds your shares.
Revoking Your Proxy or Changing Your Vote
A stockholder giving a proxy pursuant to this solicitation may revoke it at any time before it is acted upon at the 2024 Annual Meeting by (1) submitting another proxy by telephone or on the Internetinternet (only your last voting instructions will be counted); (2) sending a later dated paper proxy; (3) delivering to our Corporate Secretary a written notice of revocation prior to the voting of the proxy

Tetra Tech 2024 Proxy Statement 77

Meeting and Voting Information
at the 2024 Annual Meeting; or (4) voting in person at the 2024 Annual Meeting. Simply attending the 2024 Annual Meeting will not revoke your proxy.

Any change to your proxy provided by telephone or via the internet must be submitted by 11:59 p.m. Eastern Time on February 28, 2024.

If your shares are held in street name, you may change your vote by submitting new voting instructions to your nominee. You must contact your nominee to find out how you can change your vote.

CONFIDENTIALITY OF YOUR VOTE

              Except in contested proxy solicitations, when required by law or as expressly authorized by you (such as by making a written comment on your proxy card, in which case the comment, but not your vote, will be shared with our company), your vote or voting instruction, irrespective of method of submission, is confidential

Quorum and will not be disclosed to any other person other than the broker, trustee, agent or other person tabulating your vote. None of our directors, officers or employees will be able to access individual stockholder votes.

QUORUM AND VOTES REQUIRED

Votes Required

Votes cast by proxy or in person at the 2024 Annual Meeting will be tabulated by Broadridge Financial Solutions, Inc., the independent agent appointed as inspector of election by our Board. The inspector of election will also determine whether or not a quorum is present.
At the 2024 Annual Meeting, the existence of a quorum and tabulation of votes is determined as follows:


The presence in person or representation by proxy of a majority of the outstanding shares of common stock on the record date and entitled to vote at the 2024 Annual Meeting shall constitute a quorum for the transaction of business. Shares represented by proxies that reflect abstentions or broker non-votes (which“broker nonvotes” ​(which are shares held by a nominee that are represented and voted on a routine matter at the meeting, but with respect to which the nominee is not empowered to vote on a particular item)another nonroutine matter at the meeting) will be counted as shares that are present and entitled to vote at the 2024 Annual Meeting for purposes of determining the presence of a quorum. All of theThe items scheduled to be considered at the 2024 Annual Meeting all are "non-routine"“nonroutine” under the Nasdaqapplicable rules, except for Item 4,3, ratification of the appointment of our independent registered public accounting firm. Nominees are prohibited from voting on non-routinenonroutine items in the absence of instructions from the beneficial owners of the shares. As a result, if you hold your shares in street name and do not submit voting instructions to your nominee, your shares will be voted on Item 3 in the manner directed by your nominee, but will not be voted on Item 1, election of directors;directors or Item 2, approval,advisory vote to approve our named executive officers’ compensation, and will constitute broker nonvotes on an advisory basis, of our executive compensation; and Item 3, the approval of our 2018 Equity Incentive Plan.each such item. We urge you to promptly provide voting instructions to your nominee so that your vote is counted.

counted for Item 1 and Item 2.

Because there is no cumulative voting and this is an uncontested election, each of the director nominees named in Item 1 receiving a majority of the votes cast will be elected as a director (for these purposes, "a“a majority of votes cast"cast” means that the number of shares voted "for"“for” a director'sdirector’s election exceeds the number of votes "against"shares voted “against” that director, with abstentions not counted as votes cast)director’s election). Abstentions and broker non-votesnonvotes will not count as a vote cast for or

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        against a nominee'snominee’s election and, therefore, will have no effect in determining whether a director nominee has received a majority of the votes cast.


For Item 2, approval, on an advisory basis, ofvote to approve our named executive officers’ compensation, and Item 3, the approval of our 2018 Equity Incentive Plan, and Item 4, ratification of the appointment of our independent registered public accounting firm, the affirmative vote of the majority of the shares represented at the 2024 Annual Meeting and entitled to vote on the item will be the act of the stockholders. Abstentions as to a particular item will have the same effect as a vote against that item. Broker non-votesnonvotes will have no effect on the vote for Item 2. Ratifying the appointment of our independent registered public accounting firm is considered a routine matter on which brokers may vote in their discretion on behalf of beneficial owners. Accordingly, broker non-votesnonvotes should not be applicable forto Item 4.

VOTING ON ADDITIONAL BUSINESS

              As3. Also, Item 2 and Item 3 are advisory only and are not binding on our Company. Our Board of Directors will consider the outcome of the datevote on each of this proxy statement, we know of no other business that will be presented for consideration at the Annual Meeting. However,these items in considering what action, if any, other business properly comes before the meeting, votes willshould be casttaken in respect of any such other business in accordance with the best judgment of the persons acting pursuantresponse to the proxies.

VOTE RESULTS

advisory vote by stockholders.

Vote Results
We intend to announce preliminary voting results at the conclusion of the 2024 Annual Meeting. We expect to report final voting results in a Current Report on Form 8-K filed with the SEC on or before March 14, 2018.

PROXY SOLICITATION

              Wefour business days following the Annual Meeting.

Proxy Solicitation
Tetra Tech will bear all costs related to this solicitation of proxies. We have retained The Proxy Advisory Group, LLC to assist in soliciting proxies for a fee of $12,000, plus reimbursement for out-of-pocket expenses incident to the preparation and mailing of our proxy materials. Some of our employees may solicit proxies in person, by telephone, or by email; thesethose employees will not receive any additional compensation for their proxy solicitation efforts. We will reimburse banks, brokers, and other custodians, nominees, and fiduciaries for reasonable out-of-pocketout of pocket expenses they incur in forwarding our proxy materials to beneficial stockholders. You can help reduce these costs by electing to access proxy materials electronically.

ELECTRONIC ACCESS TO PROXY MATERIALS AND ANNUAL REPORT

Electronic Access to Proxy Materials and Annual Report
Instead of receiving paper copies of proxy statements and annual reports by mail in the future, you can elect to receive an email message that will provide a link to thesethose documents on the Internet.internet. By opting to access proxy materials via the Internet,internet, you will be

Tetra Tech 2024 Proxy Statement 78

Meeting and Voting Information
able to access them more quickly;quickly, save us the cost of printing and mailing them to you;you, reduce the amount of mail you receive from us;us, and help us preserve environmental resources.

You may enroll to access proxy materials and annual reports electronically for future Annual Meetings by registering online at the following website:www.proxyvote.com. proxyvote.com. If you vote on the Internet,internet, simply follow the prompts on the voting website to link to the electronic enrollment website.


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TIME AND LOCATION OF ANNUAL MEETING

              The Annual Meeting will take place at 10:00 a.m. Pacific Time on March 8, 2018 at the Westin Pasadena, 191 N. Los Robles Avenue, Pasadena, California 91101.

ANNUAL MEETING PROCEDURES

Procedures

You are entitled to attend the annual meeting2024 Annual Meeting if you were a stockholder of record or a beneficial owner of our common stock on January 12, 2018,2, 2024, or you hold a valid legal proxy for the annual meeting.2024 Annual Meeting. If you are a stockholder of record, you may be asked to present valid picture identification, such as a driver'sdriver’s license or passport, for admission to the annual meeting.

2024 Annual Meeting.

If your shares are registered in the name of a nominee, you may be asked to provide proof of beneficial ownership as of January 12, 2018,2, 2024, such as a brokerage account statement, a copy of the Notice of Internet Availability of Proxy Materials or voting instruction form provided by your bank, broker or other holder of record,nominee, or other similar evidence of ownership as well as picture identification for admission. If you wish to be able to vote in person at the 2024 Annual Meeting, you must obtain a legal proxy from your nominee and present it to the inspector of electionselection with your ballot.

SUBMISSION OF STOCKHOLDER ITEMS FOR 2019 ANNUAL MEETING

Submission of Stockholder Items for 2025 Annual Meeting
Requirements for Stockholder Proposals to be Considered for Inclusion in Our Proxy Materials

Our stockholders may submit proposals on matters appropriate for stockholder action at meetings of our stockholders in accordance with Rule 14a-8 promulgated under the Securities Exchange Act of 1934, as amended.Act. For such proposals to be included in our proxy materials relating tofor our 20192025 Annual Meeting, all applicable requirements of Rule 14a-8 must be satisfied and suchthe proposals must be received no later than September 26, 2018. Such20, 2024. If we change the date of the 2025 Annual Meeting by more than 30 days from the anniversary of this year’s meeting, stockholder proposals must be received a reasonable time before we begin to print and mail our proxy materials for the 2025 Annual Meeting. Proposals should be delivered to the Corporate Secretary, Tetra Tech, Inc., 3475 E. Foothill Boulevard, Pasadena, California 91107.

Requirements for Nomination of Director Candidates for Inclusion in our Proxy Materials
Our bylaws provide that if a stockholder or group of up to 20 stockholders that has continuously owned for three years at least 3% of our outstanding common stock wishes to nominate and include in our proxy materials director candidates constituting up to the greater of two individuals or 20% of our Board through our proxy access provision, stockholders must provide proper written notice of the nomination on or between August 21, 2024 and September 20, 2024, subject to the additional requirements in our bylaws. Stockholder(s) and nominee(s) must satisfy the requirements specified in the bylaws and the proxy access nomination notice must contain the information required by the bylaws. If we change the date of the 2025 Annual Meeting by more than 30 days from the anniversary of the 2024 Annual Meeting, the stockholder’s notice must be delivered no earlier than the close of business on the 120th day prior to the 2025 Annual Meeting and no later than the close of business on the later of the 90th day prior to the 2025 Annual Meeting or the 10th day following the date on which public announcement of the meeting date is first made by the Company.
Requirements for Stockholder Proposals to be Brought Before the Annual Meeting

and Nomination of Director Candidates Not Intended for Inclusion in Our Proxy Materials

Our bylaws provide that exceptstockholders seeking to present a proposal or nominate a director for election to our Board at the 2025 Annual Meeting but not intending for the proposal to be included in the case of proposals made in accordance with Rule 14a-8,proxy statement for stockholder nominations to the Board or other proposals to be considered at an annual meeting, the stockholderthat Annual Meeting must have given timely notice thereof in writing to the Corporate Secretary of Tetra Tech Inc. not lesslater than 60the close of business on the 90th day nor moreearlier than 90 daysthe close of business on the 120th day prior to the first anniversary of the date on which we mailed our proxy materials for our immediately preceding annual meeting of stockholders.year’s Annual Meeting. To be timely for the 20192025 Annual Meeting, a stockholder'sstockholder’s notice must be delivered to or mailed and received by the Corporate Secretary at our principal executive offices on or between October 26, 2018November 1, 2024, and November 25, 2018. However, inDecember 1, 2024. In the event that the annual meetingAnnual Meeting is called for a date that is not within 30 days of the anniversary of the date on which the immediately preceding annual meetingAnnual Meeting of stockholders was called,held, however, to be timely, notice by the stockholder must be so receiveddelivered not earlier than the close of business on the 120th day prior to that Annual Meeting nor later than the close of business on the tenthlater of the 90th day prior to such Annual Meeting or the 10th day following the date on which public announcement of the date of the annual meetingAnnual Meeting is first made.publicly announced. The public announcement of an adjournment of an annual meetingAnnual Meeting of stockholders will not commence a new time period for the stockholder giving of a stockholder's notice as provided above. A stockholder'sstockholder’s notice to the Corporate Secretary must set forthprovide the information required by our bylaws with respect toon each

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Meeting and Voting Information
matter the stockholder proposes to bring before the annual meeting. AsAnnual Meeting. In addition, a stockholder who intends to each person whomsolicit proxies in support of director nominees other than the stockholder proposesCompany’s nominees at the 2025 Annual Meeting must deliver written notice to nominate for election asthe Company setting forth the information required by Rule 14a-19 under the Exchange Act. If a director,stockholder’s written notice is not received between the dates specified above and does not satisfy these additional informational requirements, the notice must include:

      the name, age, business addresswill not be considered properly submitted and residence address of such nominee;

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      the principal occupation or employment of such nominee;

      the number of shares of our stock that are owned of record and beneficially by such nominee, together with the dates on which such shares were acquired and the investment intent of such acquisition;

      a statement whether such nominee, if elected, intends to tender, promptly following such person's failure to receive the required vote for election or re-electionwill not be acted upon at the next meeting at which such person would face election or re-election, an irrevocable resignation effective upon acceptance of such resignation by2025 Annual Meeting.
Pursuant to our bylaws, the Board;

information regarding the nominee that would be required to be included in our proxy statement by the ruleschairman of the SEC, includingAnnual Meeting will have the nominee's age,power and duty to determine whether a nomination or any business experience for the past five years and any other directorships held by the nominee, including directorships held during the past five years; and

the consent of the nominee to serve as a director if so elected.

              We will not permit stockholder items that do not fully comply with our notice requirementsproposed to be brought before the 2019 Annual Meeting.

              The proxy solicited by the Board for the 2019 Annual Meeting of Stockholders will confer discretionary authority to vote on (1) any proposal presented by a stockholder at that meeting for which we have not been provided with notice onwas made, or prior to November 25, 2018; and (2) on any proposal madeproposed, in accordance with the bylaw provisions, if the 2019 proxy statement briefly describes the matter and how management's proxy holders intend to vote on it, if the stockholderbylaws. Any proposed nomination or business that does not fully comply with the notice requirements of Rule 14a-4(c)(2) ofour bylaws will be disregarded and will not be brought before the Securities Exchange Act of 1934, as amended.

OTHER MATTERS

2025 Annual Meeting.

Other Matters
Our Board of Directors knows of no other matters to be presented for stockholder action at the 20182024 Annual Meeting. However, ifIf other matters properly come before the meeting or any adjournments or postponements thereof, however, the Board intends that the personsproxy holders named in the proxies will vote upon such matters in accordance with their best judgment.

BY ORDER OF THE BOARD OF DIRECTORS



Preston Hopson
Senior Vice President, General Counsel and Secretary

Pasadena, California
January 24, 2018


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APPENDIX A

2018 EQUITY INCENTIVE PLAN


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TETRA TECH, INC.
2018 EQUITY INCENTIVE PLAN

              1.           Purpose.    The purpose of the Tetra Tech, Inc. 2018 Equity Incentive Plan is to promote the interests of the Company and its stockholders by enabling the Company to offer Participants an opportunity to acquire an equity interest in the Company so as to better attract, retain, and reward its service providers and, accordingly, to strengthen the mutuality of interests between Participants and the Company's stockholders by providing Participants with a proprietary interest in pursuing the Company's long-term growth and financial success.

              2.           Definitions.    The following definitions shall be applicable throughout the Plan:

                    (a)          "Affiliate" means any entity that directly or indirectly through one or more intermediaries controls, is controlled by or is under common control with the Company as determinedsolicited by the Board in its discretion. The term "control," as used in this Plan, meanswill have the power to direct or cause the direction of the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise. "Controlled" and "controlling" have meanings correlative to the foregoing.

                    (b)          "Award" means, individually or collectively, any Incentive Stock Option, Nonqualified Stock Option, Stock Appreciation Right, Restricted Stock, Restricted Stock Unit, Stock Bonus Award, Dividend Equivalent, and Performance Compensation Award granted under the Plan.

                    (c)          "Award Agreement" means any agreement or other instrument (whether in paper or electronic medium (including email or the posting on a web site maintained by the Company or a third party under contract with the Company)) setting forth the terms of an Award that has been duly authorized and approved by the Committee.

                    (d)          "Board" means the Board of Directors of the Company.

                    (e)          "Change in Control" means the first of the following:

                        (i)           the purchase or other acquisition by any Person (as defined below), directly or indirectly, of beneficial ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act) of the Company's securities, not including the securities beneficially owned by such Person or any securities acquired directly from the Company or its Affiliates, representing 50 percent or more on a single date or during any 12 month period of the combined voting power of the Company's then outstanding voting securities entitledauthority to vote generally in the election of the Board;provided,however, that if any Person has satisfied this requirement, the acquisition of additional Company securities by the same Person shall be construed as not triggering a Change of Control; and provided further, however, that an increase in the percentage of voting securities owned by any Person as a result of a transaction in which the Company acquires its voting securities in exchange for property shall not be treated as an acquisition of the Company's voting securities for purposes of this Section 2(d)(i);

                        (ii)          the consummation of a reorganization, merger, or consolidation of the Company, if the Company's stockholders, in combination with any trustee or other fiduciary acquiring voting securities under an employee benefit plan of the Company or an Affiliate as part of such transaction, do not, immediately thereafter, own more than


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          50 percent of the combined voting power of the reorganized, merged or consolidated Company's then outstanding securities that is entitled to vote generally in the election of the directors;provided,however, that a merger or consolidation effected to implement a recapitalization of the Company (or similar transaction) in which no Person acquires more than 50 percent of the combined voting power of the Company's then outstanding securities shall not be a Change of Control under this Section 2(d)(ii); or

                        (iii)         the consummation of the sale or disposition by the Company of all or substantially all of the Company's assets in a single transaction or a series of related transactions, other than a sale or disposition by the Company of all or substantially all of the Company's assets to an entity where the outstanding securities generally entitled to vote in the election of directors of the Company immediately prior to the transaction continue to represent (either by remaining outstanding or by being converted into such securities of the surviving entity or any parent thereof) 50 percent or more of the combined voting power of the outstanding voting securities of such entity generally entitled to vote in such entity's election of directors immediately after such sale.

                    Notwithstanding the foregoing, in no event may there be more than one transaction or occurrence treated as a "Change in Control" for purposes of the Plan. In addition, if a Change in Control constitutes a payment event with respect to any Award which provides for the deferral of compensation and is subject to Section 409A of the Code, the transaction or event described in subsection (i)-(iv)proxies received with respect to such Award must also constitute a "changematters in control event," as defined in Treasury Regulation § 1.409A-3(i)(5) to the extent required by Section 409A of the Code. The Committee shall have fulltheir discretion, and final authority, which shall be exercised in its sole discretion, to determine conclusively whether a Change in Control has occurred pursuant to the above definition, and the date of the occurrence of such Change in Control and any incidental matters relating thereto.

                    (f)           "Clawback Requirements" shall have the meaning set forth in Section 15(v) of the Plan.

                    (g)          "Code" means the Internal Revenue Code of 1986, as amended, and any successor thereto. Reference in the Plan to any section of the Code shall be deemed to include any regulations or other interpretative guidance under such section, and any amendments or successor provisions to such section, regulations or guidance.

                    (h)          "Committee" means the Compensation Committee of the Board or subcommittee thereof as may be appointed by the Board under Section 4(a) of the Plan, or such other committee of the Board consisting of at least two people as the Board may appoint to administer the Plan, or, if no such committee has been appointed by the Board, the Board.

                    (i)           "Company" means Tetra Tech, Inc., a Delaware corporation, and any successor thereto.

                    (j)           "Date of Grant" means the date on which the granting of an Award is authorized, or such other date as may be specified in such authorization.

                    (k)          "Disability" means total and permanent disability as defined in Section 22(e)(3) of the Code.


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                    (l)           "Dividend Equivalent" shall mean a right to receive the equivalent value (in cash or Shares) of dividends paid on Shares, awarded under Section 10(b) of the Plan.

                    (m)        "Effective Date" means the date on which the Plan is first approved by the stockholders of the Company.

                    (n)          "Eligible Director" means a person who is (i) a "non-employee director" within the meaning of Rule 16b-3 under the Exchange Act, and (ii) an "outside director" within the meaning of Section 162(m) of the Code.

                    (o)          "Eligible Person" means any (i) individual employed by the Company or any of its Affiliates; (ii) director of the Company or any of its Affiliates; (iii) consultant or advisor to the Company or any of its Affiliates who may be offered securities registrable on Form S-8 under the Securities Act, or any other available exemption, as applicable; or (iv) prospective employees, directors, officers, consultants or advisors who have accepted offers of employment or consultancy from the Company or its Affiliates (and would satisfy the provisions of clauses (i) through (iii) above once such person begins employment with or providing services to the Company or its Affiliates).

                    (p)          "Exchange Act" means the Securities Exchange Act of 1934, as amended, and any successor thereto. Any reference in the Plan to any section of (or rule promulgated under) the Exchange Act shall be deemed to include any rules, regulations or other interpretative guidance under such section or rule, and any amendments or successor provisions to such section, rules, regulations or guidance.

                    (q)          "Exercise Price" has the meaning given such term in Section 7(b) of the Plan.

                    (r)          "Fair Market Value" means, as of any date, the value of a Share as determined by the Committee, in its discretion, subject to the following:

                        (i)           If, on such date, Shares are listed on one or more established U.S. national or regional securities exchanges, the Fair Market Value of a Share shall be the closing price of a Share as quoted on such exchange constituting the primary market for the Shares, as reported in The Wall Street Journal or such other source as the Company deems reliable (or, if no such closing price is reported, the closing bid).

                        (ii)          Notwithstanding clause (i) above, the Committee may, in its discretion, determine the Fair Market Value of a Share on the basis of the opening, closing, or average of the high and low sale prices of a Share on such date or the preceding trading day, the actual sale price of a Share, any other reasonable basis using actual transactions involving Shares as reported on an established U.S. national or regional securities exchange, or on any other basis consistent with the requirements of Section 409A of the Code.

                        (iii)         The Committee may vary its method of determining Fair Market Value as provided in this Section for purposes of different provisions under the Plan. The Committee may delegate its authority to establish Fair Market Value for purposes of determining whether sufficient consideration has been paid to exercise Options or SARs or for purposes of any other transactions involving outstanding Awards.


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                    (s)          "Immediate Family Members" shall have the meaning set forth in Section 15(b) of the Plan.

                    (t)           "Incentive Stock Option" means an Option that is designated by the Committee as an incentive stock option as described in Section 422 of the Code and otherwise meets the requirements set forth in the Plan.

                    (u)          "Indemnifiable Person" shall have the meaning set forth in Section 4(e) of the Plan.

                    (v)          "Nonqualified Stock Option" means an Option that is not designated by the Committee as an Incentive Stock Option.

                    (w)         "Option" means an Award granted under Section 7 of the Plan.

                    (x)          "Option Period" has the meaning given such term in Section 7(c) of the Plan.

                    (y)          "Participant" means an Eligible Person who has been selected by the Committee to participate in the Plan and to receive an Award pursuant to Section 6 of the Plan.

                    (z)          "Performance Compensation Award" shall mean any Award designated by the Committee as a Performance Compensation Award pursuant to Section 11 of the Plan.

                    (aa)       "Performance Criteria" shall mean the criterion or criteria under Section 11(c) that the Committee shall select for purposes of establishing the Performance Goal(s) for a Performance Period with respect to any Performance Compensation Award under the Plan.

                    (bb)       "Performance Formula" shall mean, for a Performance Period, the one or more objective formulae applied against the relevant Performance Goal to determine, with regard to the Performance Compensation Award of a particular Participant, whether all, some portion but less than all, or none of the Performance Compensation Award has been earned for the Performance Period.

                    (cc)        "Performance Goals" shall mean, for a Performance Period, the one or more goals established by the Committee for the Performance Period based upon the Performance Criteria.

                    (dd)       "Performance Period" shall mean the one or more periods of time, as the Committee may select, over which the attainment of one or more Performance Goals will be measured for the purpose of determining a Participant's right to, and the payment of, a Performance Compensation Award.

                    (ee)       "Performance Share Unit" shall mean a Restricted Stock Unit granted under Section 9 of the Plan for which vesting is partially or wholly dependent on achieving one or more performance objectives.

                    (ff)          "Permitted Transferee" shall have the meaning set forth in Section 15(b) of the Plan.

                    (gg)       "Person" means a "person" as such term is used for purposes of 13(d) or 14(d) of the Exchange Act, or any successor section thereto;provided, however, that Person shall


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      exclude (i) the Company or any of its Affiliates, (ii) any trustee or other fiduciary holding securities under an employee benefit plan of the Company or any of its Affiliates, (iii) an underwriter temporarily holding securities pursuant to an offering of such securities, and (iv) any corporation owned directly or indirectly by the stockholders of the Company in substantially the same proportion as their ownership of stock of the Company.

                    (hh)       "Plan" means the Tetra Tech, Inc. 2018 Equity Incentive Plan.

                    (ii)          "Restricted Period" means the period of time determined by the Committee during which an Award is subject to restrictions or, as applicable, the period of time within which performance is measured for purposes of determining whether an Award has been earned.

                    (jj)          "Restricted Stock" means Shares, subject to certain specified restrictions (including, without limitation, a requirement that the Participant remain continuously employed or provide continuous services for a specified period of time), granted under Section 9 of the Plan.

                    (kk)        "Restricted Stock Unit" means an unfunded and unsecured promise to deliver Shares, cash, other securities or other property, subject to certain restrictions (including, without limitation, a requirement that the Participant remain continuously employed or provide continuous services for a specified period of time), granted under Section 9 of the Plan.

                    (ll)          "SAR Period" has the meaning given such term in Section 8(b) of the Plan.

                    (mm)     "Securities Act" means the Securities Act of 1933, as amended, and any successor thereto. Reference in the Plan to any section of the Securities Act shall be deemed to include any rules, regulations or other interpretative guidance under such section, and any amendments or successor provisions to such section, rules, regulations or guidance.

                    (nn)       "Share" means a share of the Company's common stock, par value $0.01 per share.

                    (oo)       "SEC" means the Securities and Exchange Commission.

                    (pp)       "Stock Appreciation Right" or "SAR" means an Award granted under Section 8 of the Plan.

                    (qq)       "Stock Bonus Award" means an Award granted under Section 10(a) of the Plan.

                    (rr)         "Strike Price" means, except as otherwise provided by the Committee in the case of Substitute Awards, (i) in the case of a SAR granted in tandem with an Option, the Exercise Price of the related Option, or (ii) in the case of a SAR granted independent of an Option, the Fair Market Value on the Date of Grant.

                    (ss)        "Substitute Award" has the meaning given such term in Section 5(e).

              3.           Effective Date; Duration.    The Plan shall be effective as of the Effective Date. The expiration date of the Plan, on and after which date no Awards may be granted hereunder, shall be the tenth anniversary of the Effective Date;provided,however, that such expiration shall not affect Awards then outstanding, and the terms and conditions of the Plan shall continue to apply to such Awards.


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              4.           Administration.

                    (a)          The Committee shall administer the Plan. To the extent required to comply with the provisions of Rule 16b-3 promulgated under the Exchange Act (if the Board is not acting as the Committee under the Plan) or necessary to obtain the exception for performance-based compensation under Section 162(m) of the Code, as applicable, it is intended that each member of the Committee shall, at the time he takes any action with respecttheir intention to an Award under the Plan, be an Eligible Director. However, the fact that a Committee member shall fail to qualify as an Eligible Director shall not invalidate any Award granted by the Committee that is otherwise validly granted under the Plan. Unless otherwise provided in the Company's bylaws or the Committee's charter, (i) a majority of the members of the Committee shall constitute a quorum, and (ii) a vote of a majority of the members (assuming the presence of a quorum) or the unanimous written consent of the Committee members shall constitute action by the Committee.

                    (b)          Subject to the provisions of the Plan and applicable law, the Committee shall have the sole and plenary authority, in addition to other express powers and authorizations conferred on the Committee by the Plan, to: (i) designate Participants; (ii) determine the type or types of Awards to be granted to a Participant; (iii) determine the number of Shares to be covered by, or with respect to which payments, rights, or other matters are to be calculated in connection with, Awards; (iv) determine the Fair Market Value; (v) determine the terms and conditions of any Award and any amendments thereto; (vi) determine whether, to what extent, and under what circumstances Awards may vest, be settled or exercised in cash, Shares, other securities, other Awards or other property, or canceled, forfeited, or suspended and the method or methods by which Awards may be settled, exercised, canceled, forfeited, or suspended; (vii) determine whether, to what extent, and under what circumstances the delivery of cash, Shares, other securities, other Awards or other property and other amounts payable with respect to an Award shall be deferred either automatically or at the election of the Participant or of the Committee; (viii) interpret, administer, reconcile any inconsistency in, correct any defect in and/or supply any omission in the Plan and any instrument or agreement relating to, or Award granted under, the Plan; (ix) establish, amend, suspend, or waive any rules and regulations and appoint such agents as the Committee shall deem appropriate for the proper administration of the Plan; (x) accelerate the vesting or exercisability of, payment for or lapse of restrictions on, Awards; (xi) make Awards to foreign employees and others in consideration of foreign laws as contemplated by Section 15(z); and (xii) make any other determination and take any other action that the Committee deems necessary or desirable for the administration of the Plan. All powers of the Committee shall be executed in its sole discretion and need not be uniform as to similarly situated individuals.

                    (c)          Except to the extent prohibited by applicable law or the applicable rules and regulations of any securities exchange or inter-dealer quotation system on which the securities of the Company are listed or traded, the Committee may allocate all or any portion of its responsibilities and powers to any one or more of its members and may delegate all or any part of its responsibilities and powers to any person or persons selected by it. Any such allocation or delegation may be revoked by the Committee at any time. Without limiting the generality of the foregoing, the Committee may delegate to one or more officers of the Company or any of its Affiliates the authority to act on behalf of the Committee with respect to any matter, right, obligation, or election that is the responsibility of or that is allocated to the Committee herein, and that may be so delegated as a matter of law, except (i) the ability to accelerate the vesting of any Award and (ii) for grants of Awards to persons (A) who are non-employee members of the Board or otherwise are subject to Section 16 of the Exchange Act or (B) who are, or who are reasonably expected to be, "covered employees" for purposes of Section 162(m) of the Code.


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                    (d)          Unless otherwise expressly provided in the Plan, all designations, determinations, interpretations, and other decisions under or with respect to the Plan or any Award or any documents evidencing Awards granted pursuant to the Plan shall be within the sole discretion of the Committee, may be made at any time and shall be final, conclusive and binding upon all persons or entities, including, without limitation, the Company, any of its Affiliates, any Participant, any holder or beneficiary of any Award, and any stockholder of the Company.

                    (e)          No member of the Board, the Committee, delegate of the Committee or any officer, employee or agent of the Company (each such person, an "Indemnifiable Person") shall be liable for any action taken or omitted to be taken or any determination made in good faith with respect to the Plan or any Award hereunder. Each Indemnifiable Person shall be indemnified and held harmless by the Company against and from any loss, cost, liability, or expense (including attorneys' fees) that may be imposed upon or incurred by such Indemnifiable Person in connection with or resulting from any action, suit or proceeding to which such Indemnifiable Person may be a party or in which such Indemnifiable Person may be involved by reason of any action taken or omitted to be taken under the Plan or any Award Agreement and against and from any and all amounts paid by such Indemnifiable Person with the Company's approval, in settlement thereof, or paid by such Indemnifiable Person in satisfaction of any judgment in any such action, suit or proceeding against such Indemnifiable Person,provided, that the Company shall have the right, at its own expense, to assume and defend any such action, suit or proceeding and once the Company gives notice of its intent to assume the defense, the Company shall have sole control over such defense with counsel of the Company's choice. The foregoing right of indemnification shall not be available to an Indemnifiable Person to the extent that a final judgment or other final adjudication (in either case not subject to further appeal) binding upon such Indemnifiable Person determines that the acts or omissions of such Indemnifiable Person giving rise to the indemnification claim resulted from such Indemnifiable Person's fraud, gross negligence or willful criminal act or omission or that such right of indemnification is otherwise prohibited by law or by the Company's Certificate of Incorporation or Bylaws. The foregoing right of indemnification shall not be exclusive of any other rights of indemnification to which such Indemnifiable Persons may be entitled under the Company's Certificate of Incorporation or Bylaws or as a matter of law or otherwise, or any other power that the Company may have to indemnify such Indemnifiable Persons or hold them harmless.

                    (f)           Notwithstanding anything to the contrary contained in the Plan, the Board may, in its sole discretion, at any time and from time to time, grant Awards and administer the Plan with respect to such Awards. In any such case, the Board shall have all the authority granted to the Committee under the Plan.

              5.           Grant of Awards; Shares Subject to the Plan; Limitations.

                    (a)          The Committee may, from time to time, grant Options, Stock Appreciation Rights, Restricted Stock, Restricted Stock Units, Stock Bonus Awards, Dividend Equivalents and/or Performance Compensation Awards to one or more Eligible Persons.

                    (b)          Subject to Section 12, the maximum number of Shares that may be issued or transferred pursuant to Awards under the Plan will be 3,000,000 Shares. The Company may satisfy its obligations under any award granted under the Plan by issuing new shares or treasury


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      shares. The following rules apply for counting Shares against the maximum number of Shares under this Section 5(b):

                        (i)           Any Shares related to Awards that terminate by expiration, forfeiture, cancellation, or otherwise without the issuance of such Shares, are settled in cash in lieu of Shares, or are exchanged with the Committee's permission, prior to the issuance of Shares, for Awards not involving Shares, shall be available again for grant under the Plan. In addition, Restricted Stock that is forfeited shall again be available for grant under the Plan.

                        (ii)          The full number of Options and Stock Appreciation Rights granted that are to be settled by the issuance of Shares shall be counted against the number of Shares available for award under the Plan, regardless of the number of Shares actually issued upon settlement of any such Award.

                        (iii)         Any Shares withheld to satisfy tax withholding obligations on an Award issued under the Plan, Shares tendered to pay the exercise price of an Option, and Shares repurchased on the open market with the proceeds of an Option exercise will not be eligible to be again available for grant under the Plan.

                    (c)          Awards granted under the Plan shall be subject to the following limitations, which shall be subject to Section 12 of the Plan: (i) no more than 500,000 Shares may be granted as Incentive Stock Options, to any single Participant during a single calendar year; (ii) no more than 1,000,000 Shares may be subject to Options and SARs granted pursuant to Section 7 and Section 8 of the Plan to any single Participant during a single calendar year; and (iii) no more than 500,000 Shares may be subject to Performance Compensation Awards granted pursuant to Section 11 of the Plan (excluding Options and SARs) to any single Participant during a single calendar year or, in the event such Performance Compensation Award is paid in cash, other securities, other Awards or other property, no more than the Fair Market Value of 500,000 Shares on the last day of the Performance Period to which such Award relates;provided,however, that the amount of the unused annual limit with respect to the previous calendar year under the Plan beginning on or after January 1, 2019 for an Award denominated in Shares shall be added to the maximum applicable annual per-Participant Share limit.

                    (d)          At all times the Company will reserve and keep available a sufficient number of Shares to satisfy the requirements of all outstanding Awards made under the Plan and all other outstanding but unvested Awards made under the Plan that are to be settled in Shares. Shares delivered by the Company in settlement of Awards may be authorized and unissued Shares, Shares held in the treasury of the Company, Shares purchased on the open market or by private purchase, or a combination of the foregoing.

                    (e)          Awards may, in the sole discretion of the Committee, be granted under the Plan in assumption of, or in substitution for, outstanding awards previously granted by an entity acquired by the Company or its Affiliates or with which the Company or its Affiliates combines ("Substitute Awards") in a manner intended to satisfy the provisions of Section 424(a) and Section 409A of the Code. The number of Shares underlying any Substitute Awards shall not be counted against the aggregate number of Shares available for Awards under the Plan.

                    (f)           Except with respect to a maximum of (5%) of the Shares authorized under Section 5(b), as may be adjusted under Section 12, any Award granted under the Plan that vests on the basis of the Participant's continued employment with or provision of service to the


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      Company shall not provide for vesting which is any more rapid than annual pro rata vesting over a three (3) year period and any Award that vests upon the attainment of Performance Goals shall provide for a Performance Period of at least twelve (12) months, provided that vesting may be shortened in the case of death, disability, retirement or Change in Control as set forth in an Award Agreement or determined by the Committee. Notwithstanding the foregoing, this limit shall not be applicable to any Awards to newly-hired employees, Substitute Awards and non-employee members of the Board.

              6.           Eligibility.    Participation shall be limited to Eligible Persons who have entered into an Award Agreement or who have received written notification from the Committee, or from a person designated by the Committee, that they have been selected to participate in the Plan. Eligible Persons may be selected individually or by groups or categories, as determined by the Committee in its sole discretion, to participate in the Plan. An Eligible Person shall not have a right to receive an Award due to previously receiving one or more Awards under the Plan or any prior equity incentive plan maintained by the Company.

              7.           Options.

                    (a)          Generally.    Each Option granted under the Plan shall be evidenced by an Award Agreement. Each Option so granted shall be subject to the conditions set forth in this Section 7, and to such other conditions not inconsistent with the Plan as may be reflected in the applicable Award Agreement. All Options granted under the Plan shall be Nonqualified Stock Options unless the applicable Award Agreement expressly states that the Option is intended to be an Incentive Stock Option. Incentive Stock Options shall be granted only to Eligible Persons who are employees of the Company or any "parent corporation" or "subsidiary corporation" thereof within the meaning of Section 424(e) and 424(f), respectively, of the Code, and no Incentive Stock Option shall be granted to any Eligible Person who is ineligible to receive an Incentive Stock Option under the Code. No Option shall be treated as an Incentive Stock Option unless the Plan has been approved by the stockholders of the Company in a manner intended to comply with the stockholder approval requirements of Section 422(b)(1) of the Code,provided, that any Option intended to be an Incentive Stock Option shall not fail to be effective solely on account of a failure to obtain such approval, but rather such Option shall be treated as a Nonqualified Stock Option unless and until such approval is obtained. In the case of an Incentive Stock Option, the terms and conditions of such grant shall be subject to and comply with such rules as may be prescribed by Section 422 of the Code. If for any reason an Option intended to be an Incentive Stock Option (or any portion thereof) shall not qualify as an Incentive Stock Option, then, to the extent of such non-qualification, such Option or portion thereof shall be regarded as a Nonqualified Stock Option appropriately granted under the Plan.

                    (b)          Exercise Price.    Except as otherwise provided by the Committee in the case of Substitute Awards, the exercise price ("Exercise Price") per Share for each Option shall not be less than 100% of the Fair Market Value of such Share (determined as of the Date of Grant);provided,however, that in the case of an Incentive Stock Option granted to an employee who, at the time of the grant of such Option, owns stock representing more than 10% of the voting power of all classes of stock of the Company or any "parent corporation" or "subsidiary corporation" thereof within the meaning of Section 424(e) and 424(f), respectively, of the Code, the Exercise Price per Share shall not be less than 110% of the Fair Market Value per Share on the Date of Grant; andprovided,further, that a Nonqualified Stock Option may be granted with an Exercise Price lower than that set forth herein if such Option is granted pursuant to an assumption or substitution for another option in a manner satisfying the provisions of Section 424(a) and Section 409A of the Code.


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                    (c)          Vesting and Expiration.    Options shall vest and become exercisable in such manner and on such date or dates determined by the Committee and shall expire after such period, not to exceed ten years, as may be determined by the Committee (the "Option Period");provided, that if the Option Period (other than in the case of an Incentive Stock Option) would expire at a time when trading in the Shares is prohibited by the Company's insider trading policy (or Company-imposed "blackout period") or would otherwise violate an applicable federal, state, local or foreign law, the Option Period shall be automatically extended until the 30th day following the expiration of such prohibition or violation;provided,however, that the Option Period shall not exceed five years from the Date of Grant in the case of an Incentive Stock Option granted to a Participant who on the Date of Grant owns stock representing more than 10% of the voting power of all classes of stock of the Company or any of its Affiliates;provided,further, that notwithstanding any vesting dates set by the Committee, the Committee may, in its sole discretion, accelerate the exercisability of any Option.

                    (d)          Method of Exercise and Form of Payment.    No Shares shall be delivered pursuant to any exercise of an Option until payment in full of the Exercise Price therefor is received by the Company and the Participant has paid to the Company an amount equal to any federal, state, local and non-U.S. income and employment taxes required to be withheld. Options that have become exercisable may be exercised by delivery of written or electronic notice of exercise to the Companyproxies in accordance with the termsrecommendation of the Option accompanied by paymentBoard.

By order of the Exercise Price. The Exercise Price shall be payable (i) in cash, check, cash equivalent and/or Shares valued at the Fair Market Value at the time the Option is exercised (including, pursuant to procedures approved by the Committee, by meansBoard of attestation of ownership of a sufficient number of Shares in lieu of actual delivery of such Shares to the Company); or (ii) by such other method as the Committee may permit in its sole discretion, including without limitation: (A) in other property having a fair market value on the date of exercise equal to the Exercise Price, (B) if there is a public market for the Shares at such time, by means of a broker-assisted "cashless exercise" pursuant to which the Company is delivered a copy of irrevocable instructions to a stockbroker to sell the Shares otherwise deliverable upon the exercise of the OptionDirectors,
Preston Hopson
Senior Vice President, General Counsel,
and to deliver promptly to the Company an amount equal to the Exercise Price, or (C) by a "net exercise" method whereby the Company withholds from the delivery of the Shares for which the Option was exercised that number of Shares having a Fair Market Value equal to the aggregate Exercise Price for the Shares for which the Option was exercised. Any fractional Shares shall be settled in cash.

              (e)          Notification upon Disqualifying Disposition of an Incentive Stock Option.    Each Participant awarded an Incentive Stock Option under the Plan shall notify the Company in writing immediately after the date he makes a disqualifying disposition of any Share acquired pursuant to the exercise of such Incentive Stock Option. A disqualifying disposition is any disposition (including, without limitation, any sale) of such Share before the later of (i) two years after the Date of Grant of the Incentive Stock Option or (ii) one year after the date of exercise of the Incentive Stock Option.

              (f)           Compliance with Laws, etc.    Notwithstanding the foregoing, in no event shall a Participant be permitted to exercise an Option in a manner that the Committee determines would violate the Sarbanes-Oxley Act of 2002, or any other applicable law or the applicable rules and regulations of the SEC or the applicable rules and regulations of any securities exchange or inter-dealer quotation system on which the securities of the Company are listed or traded.

Secretary
Pasadena, California
January 2024


Tetra Tech 2024 Proxy Statement 80

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                    (g)          Net Exercise of In-the-Money Options on the Expiration Date.    Notwithstanding the foregoing, the Committee may provide in its sole direction and in such manner as it determines appropriate for in-the-money Options to be exercised on their expiration date (as defined below) by using a net exercise and for the Company to withhold Shares from such Award to satisfy applicable minimum tax withholding requirements. For purposes of this Section 7(g), (i) the "expiration date" shall be the last day on which an Option may be exercised under the terms of the applicable Award Agreement and (ii) an "in-the-money Option" means an Option in which the Fair Market Value of a Share is greater than the Exercise Price per Share on the expiration date.

              8.           Stock Appreciation Rights.

                    (a)          Generally.    Each SAR granted under the Plan shall be evidenced by an Award Agreement. Each SAR so granted shall be subject to the conditions set forth in this Section 8, and to such other conditions not inconsistent with the Plan as may be reflected in the applicable Award Agreement. Any Option granted under the Plan may include tandem SARs. The Committee also may award SARs to Eligible Persons independent of any Option.

                    (b)          Vesting and Expiration.    A SAR granted in connection with an Option shall become exercisable and shall expire according to the same vesting schedule and expiration provisions as the corresponding Option. A SAR granted independent of an Option shall vest and become exercisable and shall expire in such manner and on such date or dates determined by the Committee and shall expire after such period, not to exceed ten years, as may be determined by the Committee (the "SAR Period");provided,however, that notwithstanding any vesting dates set by the Committee, the Committee may, in its sole discretion, accelerate the exercisability of any SAR.

                    (c)          Method of Exercise.    SARs that have become exercisable may be exercised by delivery of written or electronic notice of exercise to the Company in accordance with the terms of the Award, specifying the number of SARs to be exercised and the date on which such SARs were awarded. Notwithstanding the foregoing, rules similar to those in Section 7(g) (regarding a Net Exercise of In-the Money Options on the Expiration Date) may be applied by the Committee in its sole discretion to SARs when the Fair Market Value of a Share is greater than the Strike Price per Share on the last day on which a SAR may be exercised under the terms of the applicable Award Agreement.

                    (d)          Payment.    Upon the exercise of a SAR, the Company shall pay to the Participant an amount equal to the number of Shares subject to the SAR that are being exercised multiplied by the excess, if any, of the Fair Market Value of one Share on the exercise date over the Strike Price, less an amount equal to any federal, state, local and non-U.S. income and employment taxes required to be withheld. The Company shall pay such amount in cash, in Shares valued at Fair Market Value, or any combination thereof, as determined by the Committee at the Date of Grant. Any fractional Shares shall be settled in cash.

              9.           Restricted Stock and Restricted Stock Units.

                    (a)          Generally.    Each grant of Restricted Stock and Restricted Stock Units shall be evidenced by an Award Agreement. Each such grant shall be subject to the conditions set forth in this Section 9, and to such other conditions not inconsistent with the Plan as may be reflected in the applicable Award Agreement.


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                    (b)          Book Entry and Stock Certificates; Escrow or Similar Arrangement.    Upon the grant of Restricted Stock, the Committee shall cause a stock certificate registered in the name of the Participant to be issued, or shall cause Shares to be registered in the name of the Participant and held in book-entry form subject to the Company's directions, and, if the Committee determines that the Restricted Stock shall be held by the Company or in escrow rather than delivered to the Participant pending the release of the applicable restrictions, the Committee may require the Participant to additionally execute and deliver to the Company (i) an escrow agreement satisfactory to the Committee, if applicable, and (ii) the appropriate stock power (endorsed in blank) with respect to the Restricted Stock covered by such agreement. If a Participant shall fail to execute an agreement evidencing an Award of Restricted Stock and, if applicable, an escrow agreement and blank stock power within the amount of time specified by the Committee, the Award shall be null and void. Subject to the restrictions set forth in this Section 9 and the applicable Award Agreement, the Participant generally shall have the rights and privileges of a stockholder as to such Restricted Stock, including without limitation the right to vote such Restricted Stock. To the extent shares of Restricted Stock are forfeited, any stock certificates issued to the Participant evidencing such Shares shall be returned to the Company, and all rights of the Participant to such Shares and as a stockholder with respect thereto shall terminate without further obligation on the part of the Company.

                    (c)          Vesting.    The Restricted Period shall lapse in such manner and on such date or dates, and, with respect to Performance Share Units, achievement of such performance results, as determined by the Committee;provided, however, that notwithstanding any vesting dates set by the Committee, the Committee may, in its sole discretion, accelerate the vesting of any Restricted Stock or Restricted Stock Units.

                    (d)          Delivery of Restricted Stock and Settlement of Restricted Stock Units.

                        (i)           Upon the expiration of the Restricted Period with respect to any shares of Restricted Stock, the restrictions set forth in the applicable Award Agreement shall be of no further force or effect with respect to such Shares, except as set forth in the applicable Award Agreement. If an escrow arrangement is used, upon such expiration, the Company shall deliver to the Participant, or his beneficiary, without charge, the stock certificate evidencing the shares of Restricted Stock that have not then been forfeited and with respect to which the Restricted Period has expired (rounded down to the nearest full Share). Participants holding shares of Restricted Stock shall be entitled to receive dividends and other distributions paid with respect to such Shares as follows unless otherwise provided in the Award Agreement:

                          (A)         If any such dividends or distributions are paid in Shares, the Shares will be subject to the same restrictions (and shall therefore be forfeitable to the same extent) as the Restricted Stock with respect to which they were paid.

                          (B)         If any such dividends or distributions are paid in cash, the Award Agreement shall specify that the cash payments shall be subject to the same restrictions as the related Restricted Stock, in which case they shall be accumulated during the Restricted Period and paid or forfeited when the related Restricted Stock vests or is forfeited.


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                           (ii)          Unless otherwise provided by the Committee in an Award Agreement, upon the expiration of the Restricted Period with respect to any outstanding Restricted Stock Units, the Company shall deliver to the Participant, or his beneficiary, without charge, one Share for each such outstanding Restricted Stock Unit;provided,however, that the Committee may, in its sole discretion, allow Participants to elect to defer the delivery of Shares beyond the expiration of the Restricted Period in compliance with Section 409A of the Code.

                       (e)          Legends on Restricted Stock.    Each certificate representing Restricted Stock awarded under the Plan shall bear a legend substantially in the form of the following in addition to any other information the Company deems appropriate until the lapse of all restrictions with respect to such Shares:

                      TRANSFERTABLE OF THIS CERTIFICATE AND THE SHARES REPRESENTED HEREBY IS RESTRICTED PURSUANT TO THE TERMSCONTENTS

    [MISSING IMAGE: cv_obc-4c.jpg]

    [MISSING IMAGE: px_24tetrapxy01pg01-bw.jpg]
    TETRA TECH, INC. 2018 EQUITY INCENTIVE PLAN AND A RESTRICTED STOCK AWARD AGREEMENT, BETWEEN TETRA TECH, INC. AND PARTICIPANT. A COPY OF SUCH PLAN AND AWARD AGREEMENT IS ON FILE AT THE PRINCIPAL EXECUTIVE OFFICES OF TETRA TECH, INC.

                  10.         Stock Bonus Awards; Dividend Equivalents.

                      (a)          Stock Bonus Awards.    The Committee may issue unrestricted Shares,C/O COMPUTERSHARE P.O. BOX 43070 PROVIDENCE, RI 02940-3070 SCAN TO VIEW MATERIALS & VOTE VOTE BY INTERNET—www.proxyvote.com or other Awards denominatedscan the QR Barcode above Use the Internet to transmit your voting instructions and for electronic delivery of information. Vote by 11:59 P.M. ET on 02/28/2024. Have your proxy card in Shares, underhand when you access the Plan to Eligible Persons, either alone or in tandem with other awards, in such amounts as the Committee shall from time to time in its sole discretion determine. Each Stock Bonus Award granted under the Plan shall be evidenced by an Award Agreement. Each Stock Bonus Award so granted shall be subject to such conditions not inconsistent with the Plan as may be reflected in the applicable Award Agreement.

                      (b)          Dividend Equivalents.    Dividend Equivalents may be granted by the Committee based on dividends declared on the Shares, to be credited as of dividend payment dates during the period between the date an Award is granted to a Participant and the date such Award vests, is exercised, is distributed or expires, as determined by the Committee. Such Dividend Equivalents shall be converted to cash or additional Shares by such formula and at such time and subject to such limitations as may be determined by the Committee. In addition, Dividend Equivalents with respect to an Award with performance-based vesting that are based on dividends paid prior to the vesting of such Award shall only be paid out to the Participant to the extent that the performance-based vesting conditions are subsequently satisfied and the Award vests. No Dividend Equivalent shall be payable with respect to any Award unless specified by the Committee in the Award Agreement.

                  11.         Performance Compensation Awards.

                      (a)          Generally.    The Committee shall have the authority, at the time of grant of any Award described in Sections 7 through 10 of the Plan, to designate such Award as a Performance Compensation Award intended to qualify as "performance-based compensation" under Section 162(m) of the Code. Notwithstanding anything to the contrary in the Plan, the Committee shall have no obligation to grant any Award in the form of "performance-based compensation" under Section 162(m) of the Code.

                      (b)          Discretion of Committee with Respect to Performance Compensation Awards.    With regard to a particular Performance Period, the Committee shall have sole


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        discretion to select the length of such Performance Period, the type(s) of Performance Compensation Awards to be issued, the Performance Criteria that will be used to establish the Performance Goal(s), the kind(s) and/or level(s) of the Performance Goals(s) that is (are) to apply and the Performance Formula. Within the first ninety (90) days of a Performance Period (or, if longer or shorter, within the maximum period allowed under Section 162(m) of the Code), the Committee shall, with regard to the Performance Compensation Awards to be issued for such Performance Period, exercise its discretion with respect to each of the matters enumerated in the immediately preceding sentence and record the same in writing.

                      (c)          Performance Criteria.    The Performance Criteria that will be used to establish the Performance Goal(s) shall be based on the attainment of specific levels of performance of the Company (and/or one or more of its Affiliates, divisions or operational and/or business units, product lines, brands, business segments, administrative departments or any combination of the foregoing) and may include any of the following: (i) net earnings or net income (before or after taxes); (ii) net income from operations; (iii) basic or diluted earnings per Share (before or after taxes); (iv) net revenue or net revenue growth (in each case, whether or not net of subcontractor costs); (v) gross revenue or gross revenue growth (in each case, whether or not net of subcontractor costs); (vi) gross profit or gross profit growth; (vii) net interest margin; (viii) operating profit (before or after taxes); (ix) return measures (including, but not limited to, return on investment, assets, capital, employed capital, invested capital, equity or sales); (x) cash flow measures (including, but not limited to, operating cash flow, free cash flow or cash flow return on capital), which may but are not required to be measured on a per-Share basis; (xi) earnings before or after taxes, interest, depreciation and/or amortization (including EBIT and EBITDA); (xii) Share price (including, but not limited to, growth measures or total stockholder return); (xiii) expense targets, cost reduction goals or general and administrative expense savings; (xiv) achieving specified improvements in collection of outstanding account receivable or specified reductions in write-offs; (xv) achieving a target days sales outstanding (DSO) level; (xvi) gross or net operating margins; (xvii) productivity ratios; (xviii) operating efficiency; (xix) measures of economic value added or other "value creation" metrics; (xx) enterprise value; (xxi) stockholder return; (xxii) client retention; (xxiii) employee retention; (xxiv) competitive market metrics; (xxv) objective measures of personal targets, goals or completion of projects (including, but not limited to, succession and hiring projects, completion of specific acquisitions, reorganizations or other corporate transactions or capital-raising transactions, expansions of specific business operations or meeting business unit or project budgets); (xxvi) objective measures of customer satisfaction; (xxvii) working capital targets; (xxviii) asset growth; (xxix) dividend yield and dividend growth; (xxx) cost of capital, debt leverage, year-end cash position or book value; (xxxi) strategic objectives, including revenue and margin targets; or (xxxii) any combination of the foregoing. Any one or more of the Performance Criteria may be stated as a percentage of another Performance Criteria, or a percentage of a prior period's Performance Criteria, or used on an absolute, relative or adjusted basis to measure the performance of the Company and/or one or more of its Affiliates as a whole or any divisions or operational and/or business units, business segments, administrative departments of the Company and/or one or more of its Affiliates or any combination thereof, as the Committee may deem appropriate, or any of the above Performance Criteria may be compared to the performance of a selected group of comparison companies, or a published or special index that the Committee, in its sole discretion, deems appropriate, or as compared to various stock market indices. The Committee also has the authority to provide for accelerated vesting of any Award based on the achievement of Performance Goals pursuant to the Performance Criteria specified in this paragraph. To the extent required under Section 162(m) of the Code, the Committee shall, within the first ninety (90) days of a Performance Period (or, if longer or shorter, within the maximum period allowed under Section 162(m) of the Code), define in an objective fashion the


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        manner of calculating the Performance Criteria it selects to use for such Performance Period and thereafter promptly communicate such Performance Criteria to the Participant.

                      (d)          Modification of Performance Goal(s).    In the event that applicable tax and/or securities laws change to permit Committee discretion to alter the governing Performance Criteria without obtaining stockholder approval of such alterations, the Committee shall have sole discretion to make such alterations without obtaining stockholder approval. The Committee is authorized at any time during the first ninety (90) days of a Performance Period (or, if longer or shorter, within the maximum period allowed under Section 162(m) of the Code), or at any time thereafter to the extent the exercise of such authority at such time would not cause the Performance Compensation Awards granted to any Participant for such Performance Period to fail to qualify as "performance-based compensation" under Section 162(m) of the Code, in its sole discretion, to adjust or modify the calculation of a Performance Goal for such Performance Period, based on and in order to appropriately reflect the following events: (i) asset write-downs; (ii) litigation or claim judgments or settlements; (iii) the effect of changes in tax laws, accounting principles, or other laws or regulatory rules affecting reported results; (iv) any reorganization and restructuring programs; (v) extraordinary nonrecurring items as described in Accounting Standards Codification Topic 225-20 (or any successor pronouncement thereto) and/or in management's discussion and analysis of financial condition and results of operations appearing in the Company's annual report to stockholders for the applicable year; (vi) acquisitions or divestitures; (vii) any other specific unusual or nonrecurring events, or objectively determinable category thereof; (viii) foreign exchange gains and losses; (ix) discontinued operations and nonrecurring charges; and (x) a change in the Company's fiscal year.

                      (e)          Payment of Performance Compensation Awards.

                          (i)           Condition to Receipt of Payment.    Unless otherwise provided in the applicable Award Agreement, a Participant must be employed by the Company or its Affiliates on the last day of a Performance Period to be eligible for payment in respect of a Performance Compensation Award for such Performance Period.

                          (ii)          Limitation.    A Participant shall be eligible to receive payment in respect of a Performance Compensation Award only to the extent that: (A) the Performance Goals for such period are achieved; and (B) all or some of the portion of such Participant's Performance Compensation Award has been earned for the Performance Period based on the application of the Performance Formula to such achieved Performance Goals.

                          (iii)         Certification.    Following the completion of a Performance Period, the Committee shall review and certify in writing whether, and to what extent, the Performance Goals for the Performance Period have been achieved and, if so, calculate and certify in writing that amount of the Performance Compensation Awards earned for the period based upon the Performance Formula. The Committee shall then determine the amount of each Participant's Performance Compensation Award actually payable for the Performance Period.

                      (f)           Timing of Award Payments.    Performance Compensation Awards that are not considered "deferred compensation" subject to Section 409A of the Code which are granted for a Performance Period shall be paid to Participants as soon as administratively practicable following completion of the certifications required by this Section 11, but in no event later than two-and-one-half months following the end of the fiscal year during which the Performance


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        Period is completed. Performance Compensation Awards that are considered "deferred compensation" subject to Section 409A of the Code shall be paid to Participants in the manner described in the applicable Award Agreement.

                  12.         Changes in Capital Structure and Similar Events.    In the event of (a) any stock dividend, extraordinary cash dividend or other distribution (whether in the form of securities or other property), recapitalization, stock split, reverse stock split, reorganization, merger, consolidation, split-up, split-off, combination, reclassification, repurchase or exchange of Shares or other securities of the Company, issuance of warrants or other rights to acquire Shares or other securities of the Company, or other similar corporate transaction or event (including, without limitation, a Change in Control) that affects the Shares, or (b) unusual or nonrecurring events (including, without limitation, a Change in Control) affecting the Company, any of its Affiliates, or the financial statements of the Company or any of its Affiliates, or changes in applicable rules, rulings, regulations or other requirements of any governmental body or securities exchange or inter-dealer quotation system, accounting principles or law, such that in either case an adjustment is determined by the Committee in its sole discretion to be necessary or appropriate, then the Committee shall make any such adjustments in such manner as it may deem equitable, including without limitation any or all of the following:

                      (i)           adjusting any or all of (A) the number of Shares or other securities of the Company (or number and kind of other securities or other property) that may be delivered in respect of Awards or with respect to which Awards may be granted under the Plan (including, without limitation, adjusting any or all of the limitations under Section 5 of the Plan) and (B) the terms of any outstanding Award, including, without limitation, (1) the number of Shares or other securities of the Company (or number and kind of other securities or other property) subject to outstanding Awards or to which outstanding Awards relate, (2) the Exercise Price or Strike Price with respect to any Award or (3) any applicable performance measures (including, without limitation, Performance Criteria and Performance Goals);

                      (ii)          subject to any limitations or reductions as may be necessary to comply with Section 409A of the Code and the regulations thereunder, providing for a substitution or assumption of Awards, accelerating the exercisability of, lapse of restrictions on, or termination of, Awards or providing for a period of time for exercise prior to the occurrence of such event; and

                      (iii)         subject to any limitations or reductions as may be necessary to comply with Section 409A of the Code and the regulations thereunder, cancelling any one or more outstanding Awards and causing to be paid to the holders thereof, in cash, Shares, other securities or other property, or any combination thereof, the value of such Awards, if any, as determined by the Committee (which if applicable may be based upon the price per Share received or to be received by other stockholders of the Company in such event), including without limitation, in the case of any outstanding Option or SAR, a cash payment in an amount equal to the excess, if any, of the Fair Market Value (as of a date specified by the Committee) of the Shares subject to such Option or SAR over the aggregate Exercise Price or Strike Price of such Option or SAR, respectively (it being understood that, in such event, any Option or SAR having a per Share Exercise Price or Strike Price equal to, or in excess of, the Fair Market Value of a Share subject thereto may be canceled and terminated without any payment or consideration therefor), or, in the case of any outstanding Restricted Stock, Restricted Stock Unit, Stock Bonus Award, or other Award denominated in Shares, a cash payment or equity subject to deferred vesting and delivery consistent with the vesting restrictions applicable to such Award or the underlying Shares subject thereto.


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    For the avoidance of doubt, in the case of any "equity restructuring" (within the meaning of the Financial Accounting Standards Board (FASB) Statement of Financial Accounting Standards Codification Topic 718, Stock Compensation), the Committee shall make an equitable or proportionate adjustment to outstanding Awards to reflect such equity restructuring. Any adjustment in Incentive Stock Options under this Section 12 (other than any cancellation of Incentive Stock Options) shall be made only to the extent not constituting a "modification" within the meaning of Section 424(h)(3) of the Code, and any adjustments under this Section 12 shall be made in a manner that does not adversely affect the exemption provided pursuant to Rule 16b-3 under the Exchange Act, to the extent applicable. The Company shall give each Participant notice of an adjustment hereunder and, upon notice, such adjustment shall be conclusive and binding for all purposes.

                  13.         Effect of Change in Control.    Except to the extent otherwise provided in an Award Agreement, in the event of a Change in Control, notwithstanding any provision of the Plan to the contrary, the Committee may provide that, with respect to all or any portion of a particular outstanding Award or Awards:

                      (a)          the then outstanding Options and SARs shall become immediately exercisable as of a time immediately prior to the Change in Control;

                      (b)          the Restricted Period shall expire as of a time immediately prior to the Change in Control (including without limitation a waiver of any applicable Performance Goals);

                      (c)          Performance Periods in effect on the date the Change in Control occurs shall end on such date, and (i) determine the extent to which Performance Goals with respect to each such Performance Period have been met based upon such audited or unaudited financial information or other information then available as it deems relevant and (ii) cause the Participant to receive partial or full payment of Awards for each such Performance Period based upon the Committee's determination of the degree of attainment of the Performance Goals, or by assuming that the applicable "target" levels of performance have been attained or on such other basis determined by the Committee; and

                      (d)          cause Awards previously deferred to be settled in full as soon as practicable.

    To the extent practicable, any actions taken by the Committee under the immediately preceding clauses (a) through (d) shall occur in a manner and at a time which allows affected Participants the ability to participate in the Change in Control transactions with respect to the Shares subject to their Awards.

                  14.         Amendments and Termination.

                      (a)          Amendment and Termination of the Plan.    The Board may amend, alter, suspend, discontinue, or terminate the Plan or any portion thereof at any time;provided, that (i) no amendment to Section 4(e) shall apply with respect to any action or omitted to be taken by an Indemnifiable Person under the Plan or any Award Agreement prior to such amendment; (ii) no amendment to Section 11(c) or Section 14(b) (to the extent required by the proviso in such Section 14(b)) shall be made without stockholder approval and (iii) no such amendment, alteration, suspension, discontinuation or termination shall be made without stockholder approval if such approval is necessary to comply with any tax or regulatory requirement applicable to the Plan (including, without limitation, as necessary to comply with any rules or requirements of any securities exchange or inter-dealer quotation system on which the Shares may be listed or quoted or to prevent the Company from being denied a tax deduction under Section 162(m) of the Code);provided,further, that any such amendment, alteration,


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        suspension, discontinuance or termination that would materially and adversely affect the rights of any Participant or any holder or beneficiary of any Award theretofore granted shall not to that extent be effective without the written consent of the affected Participant, holder or beneficiary.

                      (b)          Amendment of Award Agreements.    The Committee may, to the extent consistent with the terms of any applicable Award Agreement, waive any conditions or rights under, amend any terms of, or alter, suspend, discontinue, cancel or terminate, any Award theretofore granted or the associated Award Agreement, prospectively or retroactively;provided, that any such waiver, amendment, alteration, suspension, discontinuance, cancellation or termination that would materially and adversely affect the rights of any Participant with respect to any Award theretofore granted shall not to that extent be effective without the written consent of the affected Participant;provided,further, that without stockholder approval, except as otherwise permitted under Section 12 of the Plan, (i) no amendment or modification may reduce the Exercise Price of any Option or the Strike Price of any SAR, and (ii) the Committee may not cancel any outstanding Option or SAR in order to replace it with a new Option, SAR or other Award, and the Committee may not take any other action that is considered a "repricing" for purposes of the stockholder approval rules of the applicable securities exchange or inter-dealer quotation system on which the Shares are listed or quoted or that would result in cancellation of any Option or SAR with an Exercise Price or Strike Price, as the case may be, above the current Fair Market Value of a Share in exchange for cash or other property.

                      (c)          Extension of Termination Date.    If the exercise of the Option following the termination of the Participant's employment or service (other than upon the Participant's death or Disability) would be prohibited at any time solely because the issuance of Shares would violate the registration requirements under the Securities Act, or any other requirements of applicable law, then the Option shall terminate on the earlier of (i) the expiration of the term of the Option set forth in Section 7(c) and (ii) the expiration of a period of thirty (30) days after the termination of the Participant's employment or service during which the exercise of the Option would not be in violation of such registration requirements or other applicable requirements.

                      (d)          Restriction on Grant of Awards.    No Awards may be granted during any period of suspension or after termination of the Plan, and in no event may any Award be granted under the Plan after the tenth anniversary of the Effective Date.

                  15.         General.

                      (a)          Award Agreements.    Each Award under the Plan shall be evidenced by an Award Agreement, which shall be delivered to the Participant (whether in paper or electronic medium (including email or the posting on a web site maintained by the Company or a third party under contract with the Company)) and shall specify the terms and conditions of the Award and any rules applicable thereto, including without limitation, the effect on such Award of the death, Disability or termination of employment or service of a Participant, or of such other events as may be determined by the Committee. The terms of any Award issued hereunder shall be binding upon the executors, administrators, beneficiaries, successors and assigns of the Participant.

                      (b)          Nontransferability.

                          (i)           Each Award shall be exercisable only by a Participant during the Participant's lifetime, or, if permissible under applicable law, by the Participant's legal guardian or representative. No Award may be assigned, alienated, pledged, attached, sold or otherwise transferred or encumbered by a Participant other than by will or by the


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            laws of descent and distribution and any such purported assignment, alienation, pledge, attachment, sale, transfer or encumbrance shall be void and unenforceable against the Company or any of its Affiliates;provided, that the designation of a beneficiary shall not constitute an assignment, alienation, pledge, attachment, sale, transfer or encumbrance.

                          (ii)          Notwithstanding the foregoing, the Committee may, in its sole discretion, permit Awards (other than Incentive Stock Options) to be transferred by a Participant, without consideration, subject to such rules as the Committee may adopt consistent with any applicable Award Agreement to preserve the purposes of the Plan, to: (A) any person who is a "family member" of the Participant, as such term is used infollow the instructions to Form S-8 underobtain your records and to create an electronic voting instruction form. VOTE BY PHONE—1-800-690-6903 Use any touch-tone telephone to transmit your voting instructions. Vote by 11:59 P.M. ET on 02/28/2024. Have your proxy card in hand when you call and then follow the Securities Act (collectively, the "Immediate Family Members"); (B) a trust solely for the benefit of the Participantinstructions. VOTE BY MAIL Mark, sign and his or her Immediate Family Members; or (C) a partnership or limited liability company whose only partners or stockholders are the Participantdate your proxy card and his or her Immediate Family Members; or (D) any other transferee as may be approved either (1) by the Board or the Committee in its sole discretion, or (2) as providedreturn it in the applicable Award Agreement (each transferee described in clauses (A), (B), (C) and (D) above is hereinafter referredpostage-paid envelope we have provided or return it to as a "Permitted Transferee");provided, that the Participant gives the Committee advance written notice describing the terms and conditions of the proposed transfer and the Committee notifies the Participant in writing that such a transfer would comply with the requirements of the Plan.

                          (iii)         The terms of any Award transferred in accordance with the immediately preceding sentence shall apply to the Permitted Transferee and any reference in the Plan, or in any applicable Award Agreement, to a Participant shall be deemed to refer to the Permitted Transferee, except that (A) Permitted Transferees shall not be entitled to transfer any Award, other than by will or the laws of descent and distribution; (B) Permitted Transferees shall not be entitled to exercise any transferred Option unless there shall be in effect a registration statement on an appropriate form covering the Shares to be acquired pursuant to the exercise of such Option if the Committee determines, consistent with any applicable Award Agreement, that such a registration statement is necessary or appropriate; (C) the Committee or the Company shall not be required to provide any notice to a Permitted Transferee, whether or not such notice is or would otherwise have been required to be given to the Participant under the Plan or otherwise; and (D) the satisfaction of any applicable vesting conditions and consequences of the termination of the Participant's employment by, or services to, the Company or one of its Affiliates under the terms of the Plan and the applicable Award Agreement shall continue to be applied with respect to the Participant, including, without limitation, that an Option or SAR shall be exercisable by the Permitted Transferee only if such Option or SAR has vested due to the Participant's satisfaction of the applicable vesting criteria and only to the extent, and for the periods, specified in the Plan and the applicable Award Agreement.

                      (c)          Tax Withholding.

                          (i)           A Participant shall be required to pay to the Company or any of its Affiliates, and the Company or any of its Affiliates shall have the right and is hereby authorized to withhold, from any cash, Shares, other securities or other property deliverable under any Award or from any compensation or other amounts owing to a Participant, the amount (in cash, Shares, other securities or other property) of any required withholding taxes in respect of an Award, its exercise, or any payment or


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            transfer under an Award or under the Plan and to take such other action as may be necessary in the opinion of the Committee or the Company to satisfy all obligations for the payment of such withholding and taxes.

                          (ii)          Without limiting the generality of clause (i) above, the Committee may, in its sole discretion, permit a Participant to satisfy, in whole or in part, the foregoing withholding liability by (A) the delivery of Shares owned by the Participant having a Fair Market Value equal to such withholding liability or (B) having the Company withhold from the number of Shares otherwise issuable or deliverable pursuant to the exercise or settlement of the Award a number of Shares with a Fair Market Value equal to such withholding liability (but no more than the minimum required statutory withholding liability).

                      (d)          No Claim to Awards; No Rights to Continued Employment; Waiver.    No employee of the Company or any of its Affiliates, or other person, shall have any claim or right to be granted an Award under the Plan or, having been selected for the grant of an Award, to be selected for a grant of any other Award. There is no obligation for uniformity of treatment of Participants or holders or beneficiaries of Awards. The terms and conditions of Awards and the Committee's determinations and interpretations with respect thereto need not be the same with respect to each Participant and may be made selectively among Participants, whether or not such Participants are similarly situated. Neither the Plan nor any action taken hereunder shall be construed as giving any Participant any right to be retained in the employ or service of the Company or any of its Affiliates, nor shall it be construed as giving any Participant any rights to continued service on the Board. The Company or any of its Affiliates may at any time dismiss a Participant from employment or discontinue any consulting relationship, free from any liability or any claim under the Plan, unless otherwise expressly provided in the Plan or any Award Agreement. By accepting an Award under the Plan, a Participant shall thereby be deemed to have waived any claim to continued exercise or vesting of an Award or to damages or severance entitlement related to non-continuation of the Award beyond the period provided under the Plan or any Award Agreement, notwithstanding any provision to the contrary in any written employment contract or other agreement between the Company and its Affiliates and the Participant, whether any such agreement is executed before, on or after the Date of Grant.

                      (e)          International Participants.    With respect to Participants who reside or work outside of the United States of America and who are not (and who are not expected to be) "covered employees" within the meaning of Section 162(m) of the Code, the Committee may in its sole discretion amend the terms of the Plan or outstanding Awards with respect to such Participants in order to conform such terms with the requirements of local law or to obtain more favorable tax or other treatment for a Participant, the Company or its Affiliates.

                      (f)           Designation and Change of Beneficiary.    Each Participant may file with the Committee a written designation of one or more persons as the beneficiary(ies) who shall be entitled to receive the amounts payable with respect to an Award, if any, due under the Plan upon his death. A Participant may, from time to time, revoke or change his beneficiary designation without the consent of any prior beneficiary by filing a new designation with the Committee. The last such designation received by the Committee shall be controlling;provided,however, that no designation, or change or revocation thereof, shall be effective unless received by the Committee prior to the Participant's death, and in no event shall it be effective as of a date prior to such receipt. If no beneficiary designation is filed by a Participant, the beneficiary shall be deemed to be his or her spouse or, if the Participant is unmarried at the time of death, his or her estate.


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                      (g)          Termination of Employment/Service.    Unless determined otherwise by the Committee: (i) neither a temporary absence from employment or service due to illness, vacation or leave of absence nor a transfer from employment or service with the Company to employment or service with any of its Affiliates (or vice-versa) shall be considered a termination of employment or service with the Company or such Affiliate; and (ii) if a Participant's employment with the Company and its Affiliates terminates, but such Participant continues to provide services to the Company and its Affiliates in a non-employee capacity (or vice-versa), such change in status shall not be considered a termination of employment with the Company and its Affiliates.

                      (h)          No Rights as a Stockholder.    Except as otherwise specifically provided in the Plan or any Award Agreement, no person shall be entitled to the privileges of ownership in respect of Shares that are subject to Awards hereunder until such Shares have been issued or delivered to that person or registered in the name of that person in book-entry form.

                      (i)           Government and Other Regulations.

                          (i)           The obligation of the Company to settle Awards in Shares or other consideration shall be subject to all applicable laws, rules, and regulations, and to such approvals by governmental agencies as may be required. Notwithstanding any terms or conditions of any Award to the contrary, the Company shall be under no obligation to offer to sell or to sell, and shall be prohibited from offering to sell or selling, any Shares pursuant to an Award unless such Shares have been properly registered for sale pursuant to the Securities Act with the SEC or unless the Company has received an opinion of counsel, satisfactory to the Company, that such Shares may be offered or sold without such registration pursuant to an available exemption therefrom and the terms and conditions of such exemption have been fully complied with. The Company shall be under no obligation to register for sale under the Securities Act any of the Shares to be offered or sold under the Plan. The Committee shall have the authority to provide that all certificates for Shares or other securities of the Company or any of its Affiliates delivered under the Plan shall be subject to such stop transfer orders and other restrictions as the Committee may deem advisable under the Plan, the applicable Award Agreement, the federal securities laws, or the rules, regulations and other requirements of the SEC, any securities exchange or inter-dealer quotation system upon which such Shares or other securities are then listed or quoted and any other applicable federal, state, local or non-U.S. laws, and, without limiting the generality of Section 9 of the Plan, the Committee may cause a legend or legends to be put on any such certificates to make appropriate reference to such restrictions. Notwithstanding any provision in the Plan to the contrary, the Committee reserves the right to add any additional terms or provisions to any Award granted under the Plan that it in its sole discretion deems necessary or advisable in order that such Award complies with the legal requirements of any governmental entity to whose jurisdiction the Award is subject.

                          (ii)          The Committee may cancel an Award or any portion thereof if it determines, in its sole discretion, that legal or contractual restrictions and/or blockage and/or other market considerations would make the Company's acquisition of Shares from the public markets, the Company's issuance of Shares to the Participant, the Participant's acquisition of Shares from the Company and/or the Participant's sale of Shares to the public markets, illegal or impractical after the Company has used commercially reasonable efforts to comply with applicable law. If the Committee determines to cancel all or any portion of an Award in accordance with the foregoing, the Company shall pay to the Participant an amount equal to the excess of (A) the aggregate


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            Fair Market Value of the Shares subject to such Award or portion thereof canceled (determined as of the applicable exercise date, or the date that the Shares would have been vested or delivered, as applicable), over (B) the aggregate Exercise Price or Strike Price (in the case of an Option or SAR, respectively) or any amount payable as a condition of delivery of Shares (in the case of any other Award). Such amount shall be delivered to the Participant as soon as practicable following the cancellation of such Award or portion thereof.

                      (j)           Payments to Persons Other Than Participants.    If the Committee shall find that any person to whom any amount is payable under the Plan is unable to care for his affairs because of illness or accident, or is a minor, or has died, then any payment due to such person or his estate (unless a prior claim therefor has been made by a duly appointed legal representative) may, if the Committee so directs the Company, be paid to his spouse, child, relative, an institution maintaining or having custody of such person, or any other person deemed by the Committee to be a proper recipient on behalf of such person otherwise entitled to payment. Any such payment shall be a complete discharge of the liability of the Committee and the Company therefor.

                      (k)          Nonexclusivity of the Plan.    Neither the adoption of this Plan by the Board nor the submission of this Plan to the stockholders of the Company for approval shall be construed as creating any limitations on the power of the Board to adopt such other incentive arrangements as it may deem desirable, including, without limitation, the granting of stock options or other awards otherwise than under this Plan, and such arrangements may be either applicable generally or only in specific cases.

                      (l)           No Trust or Fund Created.    Neither the Plan nor any Award shall create or be construed to create a trust or separate fund of any kind or a fiduciary relationship between the Company or any of its Affiliates, on the one hand, and a Participant or other person or entity, on the other hand. No provision of the Plan or any Award shall require the Company, for the purpose of satisfying any obligations under the Plan, to purchase assets or place any assets in a trust or other entity to which contributions are made or otherwise to segregate any assets, nor shall the Company maintain separate bank accounts, books, records or other evidence of the existence of a segregated or separately maintained or administered fund for such purposes. Participants shall have no rights under the Plan other than as unsecured general creditors of the Company, except that insofar as they may have become entitled to payment of additional compensation by performance of services, they shall have the same rights as other employees under general law.

                      (m)        Reliance on Reports.    Each member of the Committee and each member of the Board shall be fully justified in acting or failing to act, as the case may be, and shall not be liable for having so acted or failed to act in good faith, in reliance upon any report made by the independent public accountant of the Company and its Affiliates and/or any other information furnished in connection with the Plan by any agent of the Company or the Committee or the Board, other than himself.

                      (n)          Relationship to Other Benefits.    No payment under the Plan shall be taken into account in determining any benefits under any pension, retirement, profit sharing, group insurance or other benefit plan of the Company except as otherwise specifically provided in such other plan.

                      (o)          Governing Law.    Except to the extent that provisions of the Plan are governed by applicable provisions of the Code, the Exchange Act or other substantive provisions of federal law, the Plan shall be governed by and construed in accordance with the internal laws of the State


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        of Delaware applicable to contracts made and performed wholly within the State of Delaware, without giving effect to the conflict of laws provisions thereof.

                      (p)          Severability.    If any provision of the Plan or any Award or Award Agreement is or becomes or is deemed to be invalid, illegal, or unenforceable in any jurisdiction or as to any person or entity or Award, or would disqualify the Plan or any Award under any law deemed applicable by the Committee, such provision shall be construed or deemed amended to conform to the applicable laws, or if it cannot be construed or deemed amended without, in the determination of the Committee, materially altering the intent of the Plan or the Award, such provision shall be construed or deemed stricken as to such jurisdiction, person or entity or Award and the remainder of the Plan and any such Award shall remain in full force and effect.

                      (q)          Obligations Binding on Successors.    The obligations of the Company under the Plan shall be binding upon any successor corporation or organization resulting from the merger, consolidation or other reorganization of the Company, or upon any successor corporation or organization succeeding to substantially all of the assets and business of the Company.

                      (r)          Code Section 162(m) Approval.    If so determined by the Committee, the provisions of the Plan regarding Performance Compensation Awards shall be disclosed and reapproved by stockholders no later than the first stockholder meeting that occurs in the fifth year following the year in which stockholders previously approved such provisions in order for certain Awards granted after such time to be exempt from the deduction limitations of Section 162(m) of the Code. Nothing in this clause, however, shall affect the validity of Awards granted after such time if such stockholder approval has not been obtained.

                      (s)          Other Agreements.    Notwithstanding the above, the Committee may require, as a condition to the grant of and/or the receipt of Shares under an Award, that the Participant execute lock-up, stockholder or other agreements, as it may determine in its sole and absolute discretion.

                      (t)           Payments.    Participants shall be required to pay, to the extent required by applicable law, any amounts required to receive Shares under any Award made under the Plan.

                      (u)          Non-Qualified Deferred Compensation.

                          (i)           It is intended that this Plan and Awards hereunder shall be administered, operated and interpreted in a manner so that Awards are either exempt from or comply with Section 409A of the Code. Notwithstanding any provision of the Plan to the contrary, in the event that the Committee determines that any amounts payable hereunder will be taxable to a Participant under Section 409A of the Code prior to the payment and/or delivery to such Participant of such amount, the Company may (A) adopt such amendments to the Plan and related Award Agreement, and appropriate policies and procedures, including amendments and policies with retroactive effect, that the Committee determines necessary or appropriate to preserve the intended tax treatment of the benefits provided by the Plan and Awards hereunder and/or (B) take such other actions as the Committee determines necessary or appropriate to comply with the requirements of Section 409A of the Code. It is intended that actions taken under this Plan shall not result in an Award failing to comply with Section 409A of the Code, to the extent Section 409A is applicable to such Award. However, in no event shall any member of the Board, the Company or any of its Affiliates (including their respective employees,


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            officers, directors or agents) have any liability to any Participant (or any other person) with respect to this Section 15(u).

                          (ii)          With respect to any Award that is considered "deferred compensation" subject to Section 409A of the Code, references in the Plan to "termination of employment" (and substantially similar phrases) shall mean "separation from service" within the meaning of Section 409A of the Code. For purposes of Section 409A of the Code, each of the payments that may be made in respect of any Award granted under the Plan are designated as separate payments.

                          (iii)         Notwithstanding anything in the Plan to the contrary, if a Participant is a "specified employee" within the meaning of Section 409A(a)(2)(B)(i) of the Code, no payments in respect of any Awards that are "deferred compensation" subject to Section 409A of the Code and which would otherwise be payable upon the Participant's "separation from service" (as defined in Section 409A of the Code) shall be made to such Participant prior to the date that is six months after the date of such Participant's "separation from service" or, if earlier, the Participant's date of death. Following any applicable six month delay, all such delayed payments will be paid in a single lump sum, without interest, on the earliest date permitted under Section 409A of the Code that is also a business day.

                      (v)          Claw-back Requirements.    Notwithstanding any other provision of the Plan to the contrary, in order to comply with Section 10D of the Securities Exchange Act of 1934, as amended, and any regulations promulgated, or national securities exchange listing conditions adopted, with respect thereto (collectively, the "Clawback Requirements"), if the Company is required to prepare an accounting restatement due to its material noncompliance with any financial reporting requirements under the securities laws, then the Participant shall return to the Company, or forfeit if not yet paid, the amount of any payment received with respect to an Award under the Plan during the three-year period preceding the date on which the Company is required to prepare the accounting restatement, based on the erroneous data, in excess of what would have been paid to the Participant under the accounting restatement as determined by the Committee in accordance with the Clawback Requirements and any policy adopted by the Committee pursuant to the Clawback Requirements.

                      (w)         No Liability with Respect to Any Corporate Action.    Subject to Section 15(u), nothing contained in the Plan or in any Award Agreement will be construed to prevent the Company or any of its Affiliates from taking any corporate action which is deemed by the Company or any of its Affiliates to be appropriate or in its best interest, and no Participant or beneficiary of a Participant will have any claim against the Company or any of its Affiliates as a result of any such corporate action.

                      (x)          Affiliate Employees.    In the case of a grant of an Award to an employee or consultant of any Affiliate of the Company, the Company may, if the Committee so directs, issue or transfer the Shares, if any, covered by the Award to such Affiliate, for such lawful consideration as the Committee may specify, upon the condition or understanding that the Affiliate will transfer the Shares to the employee or consultant in accordance with the terms of the Award specified by the Committee pursuant to the provisions of the Plan. All Shares underlying Awards that are forfeited or canceled shall revert to the Company.

                      (y)          Foreign Employees and Foreign Law Considerations.    The Committee may grant Awards to individuals who are eligible to participate in the plan who are foreign nationals,


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        who are located outside the United States or who are not compensated from a payroll maintained in the United States, or who are otherwise subject to (or could cause the Company to be subject to) legal or regulatory provisions of countries or jurisdictions outside the United States, on such terms and conditions different from those specified in the Plan as may, in the judgment of the Committee, be necessary or desirable to foster and promote achievement of the purposes of the Plan, and, in furtherance of such purposes, the Committee may make such modifications, amendments, procedures, or subplans as may be necessary or advisable to comply with such legal or regulatory provisions.

                      (z)          Expenses; Gender; Titles and Headings.    The expenses of administering the Plan shall be borne by the Company and its Affiliates. Masculine pronouns and other words of masculine gender shall refer to both men and women. The titles and headings of the sections in the Plan are for convenience of reference only, and in the event of any conflict, the text of the Plan, rather than such titles or headings shall control.





      TETRA TECH, INC.

      C/O COMPUTERSHARE

      P.O. BOX 43070

      PROVIDENCE, RI 02940-3070

      VOTE BY INTERNET - www.proxyvote.com

      Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 P.M. Eastern Time on March 7, 2018. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form.

      ElECTRONIC DElIVERY Of fuTuRE PROXY MATERIAlS

      If you would like to reduce the costs incurred by our company in mailing proxy materials, you can consent to receiving all future proxy statements, proxy cards and annual reports electronically via e-mail or the Internet. To sign up for electronic delivery, please follow the instructions above to vote using the Internet and, when prompted, indicate that you agree to receive or access proxy materials electronically in future years.

      VOTE BY PHONE - 1-800-690-6903

      Use any touch-tone telephone to transmit your voting instructions up until 11:59 P.M. Eastern Time on March 7, 2018. Have your proxy card in hand when you call and then follow the instructions.

      VOTE BY Mail

      Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717.

      Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS:

      KEEP THIS PORTION FOR YOUR RECORDS

      THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED.

      DETACH AND RETURN THIS PORTION ONLY

      For
      All

      Withhold
      All

      For All
      Except

      To withhold authority to vote for any individual nominee(s), mark “For All Except” and write the number(s) of the nominee(s) on the line below.

      The Board of Directors recommends you vote fOR all of the listed nominees:

      1.

      Election of Directors

      o

      o

      o

      Nominees

      01

      Dan L. Batrack

      02   Hugh M. Grant

      03   Patrick C. Haden

      04   J. Christopher Lewis

      05   Joanne M. Maguire

      06

      Kimberly E. Ritrievi

      07   Albert E. Smith

      08   J. Kenneth Thompson

      09   Kirsten M. Volpi

      The Board of Directors recommends you vote FOR proposals 2, 3 and 4.

      For

      Against

      Abstain

      2

      To approve, on an advisory basis, the Company's executive compensation;

      o

      o

      o

      3

      To approve the Company's 2018 Equity Incentive Plan;

      o

      o

      o

      4

      To ratify the appointment of PricewaterhouseCoopers LLP as the Company's independent registered public
      accounting firm for fiscal year 2018.

      o

      o

      o

      NOTE: Such other business as may properly come before the meeting or any postponement or adjournment thereof.

      Please sign exactly as your name(s) appear(s) hereon. All joint holders must sign. If signing as attorney, executor, administrator, or other fiduciary, please include full title. If a corporation or partnership, please include full corporate or partnership name and name of authorized officer signing.

      Signature [PLEASE SIGN WITHIN BOX]

      Date

      Signature (Joint Owners)

      Date

      0000351205_1 R1.0.1.17


      KEEP THIS PORTION FOR YOUR RECORDS THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. DETACH AND RETURN THIS PORTION ONLY R1.0.0.6 The Board of Directors recommends you vote FOR the following: 1. Election of Directors Nominees For Against Abstain 1A Dan L. Batrack 0 0 0 1B Gary R. Birkenbeuel 0 0 0 1C Prashant Gandhi 0 0 0 1D Joanne M. Maguire 0 0 0 1E Christiana Obiaya 0 0 0 1F Kimberly E. Ritrievi 0 0 0 1G Kirsten M. Volpi 0 0 0 The Board of Directors recommends you vote FOR For Against Abstainproposals 2 and 3.2 To approve, on an advisory basis, the Company’s 0 0 0 named executive officers’ compensation. 3 To ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2024. NOTE: In their discretion, the proxies are authorized to vote on such other business as may properly come before the meeting or any postponement or adjournment thereof. For Against Abstain 0 0 0 Please sign exactly as your name(s) appear(s) hereon. All joint holders must sign. If signing as attorney, executor, administrator, or other fiduciary, please include full title. If a corporation or partnership, please include full corporate or partnership name and name of authorized officer signing. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date


      Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice & Proxy Statement, Annual Report and Shareholder Letter are available at www.proxyvote.com

      TETRA TECH, INC.

      Annual Meeting of Stockholders

      March 08, 2018, 10:00 AM Pacific Time

      This proxy is solicited by the Board of Directors

      This proxy, when properly executed, will be voted in the manner directed herein or, if no such direction is made, this proxy will be voted in accordance with the Board of Directors' recommendations with respect to the election of directors and proposals 2, 3 and 4, and in the discretion of the proxy holder(s) as to any other matters that may properly come before the Annual Meeting or any postponement or adjournment of the Annual Meeting.

      The stockholder(s) hereby revoke(s) all prior proxies to vote at the Annual Meeting or any postponement or adjournment thereof and appoint(s) Dan L. Batrack and Richard A. Lemmon, and each of them, as proxies, each with full power of substitution, and hereby authorize(s) each of them to represent and to vote, as designated on the reverse side of this ballot and any other matters which may properly come before the Annual Meeting and all postponements or adjournments of the Annual Meeting, all of the shares of common stock of TETRA TECH, INC. that the stockholder(s) is/are entitled to vote at the Annual Meeting to be held at 10:00 AM Pacific Time on 03/08/2018, at the Westin Pasadena, 191 N. Los Robles Avenue, Pasadena, CA 91101, and any postponement or adjournment thereof.

      Complete and sign on the reverse side

      0000351205_2 R1.0.1.17


      [MISSING IMAGE: px_24tetrapxy01pg02-4c.jpg]
      Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice & Proxy Statement, Annual Report, Shareholder Letter are available at www.proxyvote.com TETRA TECH, INC. Annual Meeting of Stockholders February 29, 2024 10:00 AM This proxy is solicited by the Board of Directors The stockholder(s) hereby revoke(s) all prior proxies to vote at the Annual Meeting or any postponement or adjournment thereof and appoint(s) Dan L. Batrack and Preston Hopson, and each of them, as proxies, each with full power of substitution, and hereby authorize(s) each of them to represent and to vote, as designated on the reverse side of this ballot and any other matters which may properly come before the Annual Meeting and all postponements or adjournments of the Annual Meeting, all of the shares of common stock of TETRA TECH, INC. that the stockholder(s) is/are entitled to vote at the Annual Meeting to be held at 10:00 AM Pacific Time on 02/29/2024, at Westin Pasadena, 191 North Los Robles Avenue, Pasadena, CA 91101, and any postponement or adjournment thereof. This proxy, when properly executed, will be voted in the manner directed herein or, if no such direction is made, this proxy will be voted in accordance with the Board of Directors’ recommendations with respect to the election of directors and proposals 2 and 3, and in the discretion of the proxy holder(s) as to any other matters that may properly come before the Annual Meeting or any postponement or adjournment of the Annual Meeting. PLEASE MARK, SIGN, DATE AND RETURN THIS PROXY CARD PROMPTLY USING THE ENCLOSED POSTAGE-PAID ENVELOPE. IF YOU CHOOSE TO VOTE BY TELEPHONE OR INTERNET, DO NOT RETUN THIS PROXY. R1.0.0.6 Continued and to be signed on reverse side


      0000831641 4 2022-10-03 2023-10-01