Tetra Tech to Present at the FBR Capital Markets 2008 Fall Investor Conference

Tetra Tech, Inc. (NASDAQ: TTEK) announced today that David King, Executive Vice President and Chief Financial Officer, and Jorge Casado, Director of Investor Relations, will give a presentation to investors at the FBR Capital Markets 2008 Fall Investor Conference in New York City on Wednesday, December 3, 2008, at 8:30 a.m. Eastern Time. Tetra Tech invites investors and other interested parties to attend a live webcast of its presentation. The webcast and a copy of the presentation slides will be available on the Company’s website at www.tetratech.com. A replay of the presentation will be available on the website following the presentation.

About Tetra Tech (www.tetratech.com)

Tetra Tech is a leading provider of consulting, engineering, and technical services. With approximately 8,500 associates located in the United States and internationally, the Company supports commercial and government clients in the areas of resource management and infrastructure. Tetra Tech’s services include research and development, applied science and technology, engineering design, program management, construction management, construction, and operations and maintenance.

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.