for Controlling Toxic Chemicals in Small Streams

Stormwater management professionals in local jurisdictions need tools to develop plans for flow and pollution control to meet water-quality goals. SUSTAIN (System for Urban Stormwater Treatment and Analysis INtegration) is a computer model developed by the federal Environmental Protection Agency to test the efficacy of Best Management Practices (BMPs) for keeping toxic chemicals out of small streams in urban watersheds. SUSTAIN was developed by EPA as a decision-support system to facilitate the selection and placement of BMPs and Low Impact Development techniques at strategic locations.

The Department of Ecology and its partners tested SUSTAIN as a tool for watershed planners and others to learn how effective BMPs are in reducing runoff and pollutant loadings to the Puget Sound through a case study carried out in Federal Way, Washington in 2012. They convened a Project Advisory Group in 2011 and 2012 to inform the project. Funding was through EPA’s National Estuary Program under the Controlling Toxic Chemicals in Puget Sound project (Phase 3, Subtask 3B). The final report for this component is complete, as is the cost database developed to accompany this work.

Case Study for Applying SUSTAIN to a Small Watershed in the Puget Lowland is the final report of this project applying a real-world example of how to maximize water quality benefits and minimize stormwater management costs in subbasins with established water quality problems. They assessed flow-control improvements to test the model.

Puget Sound Stormwater BMP Cost Database is an attachment to the above report. It describes costs for best management practices (BMPs) installed in the Puget Sound region.

SUSTAIN Workshop: SUSTAIN Model Evaluation is a PDF slideshow, originally given at a Project Advisory Committee workshop in December 2012. It is a summary of the modeling methods, results, lessons learned, and the limitations that were discovered by this study.

Quality Assurance Project Plan: Phase 3: SUSTAIN Modeling for Controlling Toxic Chemicals in Small Streams describes the methods used to study the model.

Advisory Group Kickoff Meeting presentation from the advisory group kickoff meeting in July 2011 discusses the demonstration project to develop and implement a surface runoff modeling tool.

Environmental Information Management (EIM) #PSTox001 contains the data for the project.

For more information contact Mindy Roberts at or call 360-407-6804.

Related Information

Controlling Toxic Chemicals in Puget Sound describes the larger NEP-funded project.

Saving Puget Sound describes the larger agency initiative.

Sound Science is a page that describes monitoring and modeling efforts in Puget Sound.

Modeling the Environment is a page about environmental computer modeling projects at the Department of Ecology.

Water Resource Inventory Area 09 Duwamish-Green contains more information about the study-area watershed.