Tetra Tech to Present at Two Investor Conferences in February

Tetra Tech, Inc. (NASDAQ: TTEK) announced today that David King, Executive Vice President and Chief Financial Officer, and Jorge Casado, Vice President of Investor Relations, will give a presentation to investors at two conferences this month. On Tuesday, February 23, 2010 at 8:30 a.m. eastern time, the Company will present at the Piper Jaffray Clean Technology & Renewables Conference in New York City, and on Wednesday, February 24, 2010 at 12:05 p.m. eastern time, the Company will present at the Baird Business Solutions Conference in Boston. Tetra Tech invites investors and other interested parties to attend live webcasts of these presentations. The webcasts and a copy of the presentation slides will be available on the Company’s website at www.tetratech.com. A replay of the presentations will be available on the website following the presentation.

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 approximately 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.