Skip to main content
King County logo

Completed – Fall 2015

King County is responsible for regular maintenance of the roadside rain gardens year round. You can expect to see crews onsite at least monthly performing regular maintenance. Expect more frequent visits before and after large storms, and during the summer growing season.

Learn more by visiting the operations page for the Barton CSO control facility (roadside rain gardens).

Project description

King County constructed 91 roadside rain gardens, a type of green stormwater infrastructure, on 15 blocks in the Sunrise Heights and Westwood neighborhoods in West Seattle. Located in the planter strip between the curb and sidewalk, these roadside rain gardens divert stormwater runoff away from the combined sewer system. When it rains, stormwater filters through the rain garden soil to a drain pipe, which takes the water to a deep well for slow infiltration underground. Keeping stormwater out of the sewer system will reduce CSOs of raw sewage and untreated stormwater into Puget Sound near the recently upgraded Barton pump station and Fauntleroy ferry dock.

Summer 2015 newsletterLearn more: view the Summer 2015 project newsletter 


Barton-CSO-Project-MapSource: summer 2015 newsletter 


24-hour emergency and odor reporting:

Contact West Point Treatment Plant at  206-263-3801.

24-hour maintenance hotline, 206-263-3801

King County has installed curb markers on every block with information on how to contact the County with questions or concerns about the rain gardens. Please call 206-263-3801 if you see:

  • Ponding water that lasts longer than 24 hours after it has stopped raining
  • Vandalism
  • Spills or contamination
  • Other major concerns

Project location


If you see a piece of trash, pick it up. Thank you for your ongoing care of the roadside rain gardens in your neighborhood. You are doing your part to protect the health of Puget Sound!

The Barton CSO Control Project is featured in a video about rain gardens and green stormwater infrastructure (GSI) by Sightline Institute 

Find out if a CSO is occurring in Barton

King County maintains a real-time notification page so people can see whether CSO discharges are occurring.

Related content

Protecting our waters (Combined Sewer Overflow Control Program), King County


You can download and view documents (PDF files) using a PDF Reader.

Barton and Murray (West Seattle) CSO Control Facilities Plan

Facilities Plan Cover - Barton and Murray CSO Control, Draft, February 2011King County has developed proposals to control combined sewer overflows (CSOs) at two locations in West Seattle—the Barton and Murray CSO basins. One project is the construction of a new 1.0-million-gallon storage tank on the east side of Beach Drive SW near Lowman Beach Park to control CSOs in the Murray CSO basin. The other is the installation of rain gardens in the right-of-way along 32 to 64 half-blocks in the Sunrise Heights and Westwood neighborhoods east of 35th Avenue SW to control overflows in the Barton CSO basin.

The Barton and Murray Combined Sewer Overflow Control Facilities Plan describes the reasons for these projects, the processes used to develop and evaluate alternatives, and the selection of proposed alternatives to advance for further environmental review. These projects are necessary to control CSOs in compliance with RCW 90.48.480 and WAC 173-245-020 (22).

This plan is submitted in compliance with the first of three compliance schedule dates noted in Section S18 of the West Point Treatment Plant National Pollutant Discharge Elimination System Permit (refer to page 53 of permit).

Final Facility Plan, September 2011

Draft Facilities Plan, February 2011

This project was initiated to address the following:

  • Revised Code of Washington (RCW) 90.48.480: This law requires “the greatest reasonable reduction of combined sewer overflows.”
  • Washington Administrative Code (WAC) 173-245-020 (22): “The greatest reasonable reduction’ means control of each CSO in such a way that an average of one untreated discharge may occur per year.”

Links to other green stormwater infrastructure (GSI) projects and resources locally, regionally and around the country.



  • Case studies, Portland Bureau of Environmental Services, Oregon