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King Street Center
201 S. Jackson St., Suite 500
Seattle, WA 98104-3855
Phone: 206-684-1280
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Staff Contacts

Puget Sound shoreline next to the West Point Treatment Plant, Seattle

Murray CSO control project

Project design

April 2012 Update
Murray CSO Design Advisory Group - Meeting #6
Thursday, May 10, 2012
6:30 – 8:30 p.m.,
Fauntleroy Church, 9140 California Ave SW, Seattle
Agenda items include:
• Review of SDOT meetings
• Discussion on revised design concept
• Public art process
• Site security/building deconstruction

Murray basin and project location
Murray basin and project location

Murray CSO basin project area
Murray CSO basin project area

Project description

King County plans to design and build an underground storage tank beneath private property across the street from Seattle’s Lowman Beach Park. This facility will store approximately one million gallons of peak flows when the Murray Pump Station reaches maximum capacity.

Learn how the underground storage tank will work to limit discharges of untreated wastewater and stormwater to Puget Sound (PDF).

Why does King County need to do this project?

Like many cities around the country (external link), the older parts of King County's wastewater system carry both wastewater and stormwater to the treatment plant. When heavy rains fill the pipes, excess stormwater and sewage flow directly into Puget Sound near the Murray Pump Station. These events, called combined sewer overflows (CSOs), consist of about 90 percent stormwater and the rest is dilute sewage. CSOs help to avoid sewer backups into homes and businesses and onto streets during storms, but they are a public health and environmental concern.

King County is building the Murray CSO control facility to reduce overflows into Puget Sound. State regulations require no more than one untreated discharge per year. The Murray Pump Station averages five untreated CSO events per year, discharging 5 million gallons into Puget Sound off of Lowman Beach Park.

Project Schedule

December 30, 2010
Submited draft Facility Plan to Department of Ecology

2011-2015

Community outreach

April-May 2011

SEPA threshold determined and public comment period

July 1, 2011

Ecology approves Facility Plan

Spring-Summer 2011

Design team formed

Fall 2011-early 2012

Preliminary design

Fall 2011-Fall 2012

Permitting

Spring - Summer 2012

Removal of existing structures in project area
2012
Final design
2012
Ecology approves final design
2013-2014
Construction

View project meeting calendar.

What is next?

King County will work closely with the West Seattle community throughout the project. The public an inform the County's decision about some project elements including facility architecture and landscaping.

News releases

Project updates 

Find out if a CSO is occurring in Murray

Related information

For more information