We lead projects to measure, monitor and improve water quality in the many streams and rivers that drain into Puget Sound. Because water flows across geographical and political boundaries, water areas are identified not by county or city, but by a common point to which they drain. These water areas are called watersheds and basins.  Watershed and basin studies help Thurston County government identify specific projects that can reduce the amount of pollution in water, and lessen the effects of polluted runoff on area drinking water aquifers, and on frog, fish and shellfish habitat. The County's pollution reduction activities are mandated and monitored by the U.S. Environmental Protection Agency and by the Washington State Legislature.  Find details on the Stormwater Management Program page.