Tetra Tech Awarded $25 Million EPA Water Contract

Tetra Tech, Inc. (NASDAQ:TTEK) announced today that it has been awarded a $25 million contract with the U.S. Environmental Protection Agency (EPA) Pacific Southwest Region (Region 9) Water Division. The new contract expands Tetra Tech’s technical support of EPA’s west coast watershed and coastal protection programs, including its pollution prevention and sustainable water infrastructure activities. The contract has a five-year period of performance and will include time and materials and fixed-price tasks.

Tetra Tech will help EPA and its state, territory, and tribal partners to integrate and implement core water programs associated with the Clean Water Act, the Marine Protection and Sanctuaries Research Act, and the Safe Drinking Water Act. Tetra Tech will also help EPA promote sustainable water infrastructure practices through energy efficiency, water efficiency, green infrastructure, and other innovative environmental projects.

About EPA Region 9 Water Division (www.epa.gov/region/water)

EPA Region 9 serves the Pacific Southwest, including Arizona, California, Hawaii, Nevada, the Pacific Islands, and Tribal Nations. The Water Division is responsible for providing clean and safe surface water, groundwater, and drinking water and protecting and restoring aquatic ecosystems.

About Tetra Tech (www.tetratech.com)

Tetra Tech is a leading provider of consulting, engineering, program management, construction, and technical services addressing the resource management and infrastructure markets. The Company supports government and commercial clients by providing innovative solutions focused on water, the environment, and energy. With more than 10,000 employees worldwide, Tetra Tech’s capabilities span the entire project life cycle.

Any statements made in this release that are not based on historical fact are forward-looking statements. Any forward-looking statements made in this release represent management’s best judgment as to what may occur in the future. However, Tetra Tech’s actual outcome and results are not guaranteed and are subject to certain risks, uncertainties and assumptions ("Future Factors"), and may differ materially from what is expressed. For a description of Future Factors that could cause actual results to differ materially from such forward-looking statements, see the discussion under the section "Risk Factors" included in the Company’s Form 10-K and 10-Q filings with the Securities and Exchange Commission.