Deschutes Watershed Study

Thurston County government received a grant from the U.S. Environmental Protection Agency to study regulatory ways to protect and improve water quality in the Deschutes River watershed. The County formed a work group with the Squaxin Island Tribe; cities of Olympia, Rainier, and Tumwater; and the Thurston Regional Planning Council. The group detailed existing conditions; studied effects of various land management scenarios on water quality; presented proposals to public and stakeholder groups, and incorporated the input received; and finally recommended land management and regulatory strategies for the watershed. Their recommendations were approved in Resolution 15374 (PDF) by Thurston's Board of County Commissioners on November 29, 2016. 

Study dates  2015-2016

Completed Work

​Reports & Survey (PDFs)
​Final Report with Scenario Development
​​Current Conditions Report
Community Survey 
​Maps (PDFs)

Map 1  Project Study Area
​Map 14 Well Logs
Map 27 TMDL Shade Improvement
Map 2  Basins
​Map 15 Landcover
Map 28 TMDL Bacteria MS
Map 3  Soils
​Map 16 Landuse
​Map 29 TMDL Bacteria OA
​Map 4  Seepage
Map 17 Sewer
​Map 30 TMDL DO Improvement
​Map 5  Critical Areas
​Map 18 Current Conditions
​Map 6  TCD Shade
​Map 19 Impervious 1991
​Map 32 TMDL Fine Sediment
​Map 7  303d List
​Map 20 Impervious 2010
Map 33 Development
​Map 8  Urban Septic System Analysis Area
Map 21 Impervious Buildout
​Map 34 Zoning
​Map 9  Urban Septic System Analysis Groundwater Risk (Revised March 2014)
Map 22 Canopy 2006
​Map 35 OSTP
Map 10  Urban Septic System Analysis Surface Water Risk
Map 23 PSWC Flow Ooverall MZ
Map 36 Forest Vulnerability
​Map 11  Urban Septic System Analysis Neighborhood Density
Map 24 PSWC WQ Deg
​Map 37 Agriculture
Map 12  Urban Septic System Analysis Groundwater Risk Scores All Neighborhoods
Map 25 PSWC FW Salmon
​Map 38 Priority Areas
​Map 13  Urban Septic System Analysis Surface Water Risk Scores All Neighborhoods
Map 26 PSWC Terrestrial


The Deschutes River is one of the largest streams in Thurston County. It flows more than 57 miles from its forested headwaters to Puget Sound. The watershed that drains into the river includes a variety of land uses, including timberand agricultural lands, as well as developed areas within the cities ofOlympia and Tumwater. While the Deschutes River currently supports avariety of wildlife habitat and recreational uses, it also suffers from ongoing pollution concerns. The river is listed under the federal Clean Water Act for dissolved oxygen, fecal coliform, temperature, pH, andfine sediment, and is the subject of a state-coordinated cleanup plan. Nutrient levels in the Deschutes contribute to pollution issues in Capitol Lake, and it is considered a major contributor to low dissolved oxygen levels in Budd Inlet. Anticipated future development in the watershed could exacerbate waterquality issues.

Public Outreach
A stakeholder group informed the development of alternative future scenarios, and considered the impactsof different land use management options on water quality and other factors in the watershed. The project team presented the alternative future scenarios and recommended land use management options from the stakeholder workgroup at a community workshop on June 30, 2016 and incorporated input from the public and residents of the watershed in the final recommendations.

Meeting Date
​Meeting Materials (PDFs)
​September 2, 2016  (Stakeholder group)
Meeting Summary
​June 30, 2016  (Community workshop)
Community Workshop Presentation
​June 2, 2016  (Stakeholder group)
Meeting Summary
Presentation - Scenario Results
​March 25, 2016  (Stakeholder group)
Meeting Summary
Presentation - Concerns & Scenarios
​January 29, 2016  (Stakeholder group)
Meeting Summary
Presentation - Management Tools
Presentation - Voluntary Approaches
​December 11, 2015  (Stakeholder group)
Meeting Summary
Presentation - Project Overview