PASADENA, CA, Oct. 16, 2012 -- Tetra Tech Inc. (NASDAQ: TTEK) announced that it has been awarded a $108 million contract to provide technical support for the U.S. Environmental Protection Agency Office of Water. Tetra Tech will assist the EPA Office of Water's Assessment and Watershed Protection Division in its efforts to assess and monitor water quality conditions, implement point and nonpoint source pollution controls and develop tools for ecosystem restoration, among other efforts. This watershed protection program is considered one of the principal technical support focuses of the EPA Office of Water. The multiple-award contract has a five-year period of performance.

The new contract expands Tetra Tech's watershed protection work with the EPA Office of Water, an agency office that Tetra Tech has supported for more than 30 years. The EPA Office of Water works with the 10 EPA regional offices, other federal agencies, state and local governments, regulated commercial interests and the public, among other stakeholders.

About the EPA Office of Water (www.epa.gov/aboutepa/ow)

The Office of Water ensures drinking water is safe and restores and maintains oceans, watersheds and their aquatic ecosystems to protect human health, support economic and recreational activities and provide healthy habitat for fish, plants and wildlife. The Office of Water is responsible for implementing the Clean Water Act and Safe Drinking Water Act, among other federal water and water-related statutes.

About Tetra Tech (www.tetratech.com)

Tetra Tech is a leading provider of consulting, engineering, program management, construction management and technical services. The Company supports government and commercial clients by providing innovative solutions to complex problems focused on water, environment, energy, infrastructure and natural resources. With more than 13,000 employees worldwide, Tetra Tech's capabilities span the entire project life cycle.

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