Water Quality in the Puget Sound Basin
Surface Water Studies
Purpose
Assess the quality of some of the more than 100 streams and rivers that discharge to Puget Sound and incorporate this information into the U.S. Geological Survey (USGS) national assessment of water quality. Three major components include:
Retrospective Studies (1995)
Provide a first-cut analysis of general water-quality conditions within the study unit using existing water-quality data. Information on the occurrence and distribution of nutrients and pesticides in Puget Sound Basin streams was used to:
- Calculate the nutrient loads from major rivers to Puget Sound
A large existing nutrient data set collected primarily by the Washington State Department of Ecology (Ecology), the USGS, and King County METRO allowed the calculation of average annual nutrient loads (inorganic nitrogen and phosphorus) for the major rivers discharging to Puget Sound. These loading estimates reveal water-quality differences between major watersheds in the Basin and allow estimates of total nutrient input to Puget Sound from surface-water sources. The results of these studies are contained in a report and a fact sheet.
- Evaluate the occurrence and distribution of pesticides in small streams draining predominantly agricultural and urban land uses in the Puget Sound Lowland.
Pesticides have been sampled for in small streams in the Puget Sound Lowland in recent years by Ecology, the U.S. Environmental Protection Agency, and researchers from Western Washington University. In association with Ecology, Puget NAWQA staff aggregated this information into a regional analysis of pesticide occurrence in streams draining urban and agricultural land uses. Results are summarized in a fact sheet: Pesticides in Selected Small Streams in the Puget Sound Basin, 1987-1995, Bortleson, G. C., U.S . Geological Survey, and Davis, D. A., Washington State Department of Ecology, U.S. Geological Survey Fact Sheet 067-97, 4 p.
- Summarize existing information on aquatic biota
Monitoring fish and benthic invertebrate communities, assessing aquatic habitat, and analyzing for contaminants in fish tissue have been done by Ecology, researchers from the University of Washington and Western Washington University, U.S. Forest Service, U.S. Army Corps, the Salmon and Steelhead Habitat and Assessment Project, and U.S. Environmental Protection Agency. Puget NAWQA biologists compiled basin-wide information and data and evaluated the status and trends of aquatic biota, summarized factors affecting aquatic biota, and provided a topical bibliography in the report Water Quality Assessment of the Puget Sound Basin, Summary of Stream Biological Data Through 1995.
Fixed Station Water-Quality Sampling (1995-1998)
Eleven sites -- Thornton Creek in the Lake Washington basin and 10 stations in the Nooksack, Green, and Skokomish River basins-- are sampled at least once a month to:
- Evaluate the integrated effects of various land uses on water quality, using data from sites located near the mouths of watersheds
- Evaluate the specific effects of individual land uses, using sites located in smaller upstream watersheds comprised of predominantly forested, agricultural, suburban, or urban land uses.
- The results of samples collected for chemical analysis and relations of water quality to land uses are detailed in a final report.
Synoptic Sampling (1998)
Evaluate the distribution of an individual water-quality constituent or group of constituents over a geographically dispersed area. Two studies were conducted in 1998:
Low Intensive Phase Sampling (1998-2004)
Selected study sites are monitored during the low-intensity phase to obtain data necessary for future evaluation of long-term trends in water quality. Monthly water samples are collected at three study sites - Thornton Creek, Duwamish River, and North Fork Skokomish River.
For information about Surface Water in the Puget Sound Basin, please contact Sandra Embrey, Hydrologist, at (253) 428-3600 (x2644).
U.S. Department of the Interior |
U.S. Geological Survey