Joe Brascher and Doug Beyerlein of Clear Creek Solutions provided the King County Department of Natural Resources and Parks, Water and Land Resources Division with HSPF modeling services to develop a water quantity and quality analysis models for two topographic basins - the Green-Duwamish and the Lake Washington-Ship Canal basins. These models support the two major projects: the Green-Duwamish Water Quality Assessment (GDWQA) and the Sammamish-Washington Analysis and Modeling Program (SWAMP). They are integrated components of an overall modeling system of both watersheds and major receiving water processes including hydrodynamics, water quality, and bio-dynamics within the Duwamish River and Lakes Sammamish, Washington, and Union.

The primary purpose of the watershed water quality and quantity models is to support the GDWQA and SWAMP teams by simulating at a tributary level, surface and subsurface flow and associated physical, chemical, and biological loads to major receiving waters -- the Green River and Duwamish Estuary for the GDWQA and the major lakes for the SWAMP under a range of land use and infrastructure scenarios. Additionally these models provide a general tool for watershed analysis, management and educational outreach components of SWAMP and GDWQA, King County's ESA-response, aquatic resource protection, stormwater management programs, and ecological and human health risk assessment.