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Stormwater monitoring and treatment

King County Road Services - Stormwater monitoring and treatment

Overview

Western Washington is no stranger to rain. When rain falls, it flows over roofs, lawns, roads, fields and other surface features before entering the stormwater conveyance system and discharging into receiving water bodies. Stormwater has the potential to pick up various chemicals and pollutants along the way, which may impact water quality in local streams, lakes, rivers, and even Puget Sound.

King County Road Services maintains an extensive network of catch basins, drainage pipes, and ditches throughout unincorporated King County that convey stormwater from the road right-of-way and adjacent properties. Therefore, we have an interest in monitoring and mitigating the effects of stormwater runoff on water quality in our region.

Improving stormwater quality within roadside ditches

Stormwater is conveyed in roadside ditches throughout much of unincorporated King County.

In 2008, the Washington State Department of Ecology awarded the King County Road Services Division, Roads Maintenance Section grant funding to try to answer this question: "Is it feasible to improve water quality in roadside ditches?"

We used the grant funds to (1) research and compile existing literature and studies on stormwater treatment and (2) to design and install simple, low-cost, low-maintenance stormwater Best Management Practices (BMPs) in roadside ditches and evaluate their performance based on monitoring data. Learn more about these efforts:

Watch a video clip about treating stormwater in roadside ditches

Stormwater ditch video
Roadside ditch stormwater pollution filtering video

Have questions?

If you have questions about our stormwater monitoring and treatment efforts, or if you would simply like more information, please contact:

Environmental Unit
King County Roads Maintenance Section
155 Monroe Ave. N.E.
Renton, WA 98056
206-205-7107


Information from the Road Services Division's website is available to people with disabilities in alternate formats upon request by calling 206-263-6482 or 711 for the TTY relay service.

External link = External link

Final report

Final report
In-Line Ditch
Stormwater Treatment
BMP Program Final Report


Also see

King County Stormwater Management Program
King County Stormwater
Management Program

npdes
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of ROAD MAP

(61KB .pdf)


What you can do

WhatYouCanDo
Stormwater runoff -
what you can do

Learn about stormwater runoff
and steps you can take
to help minimize
stormwater pollution.