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King Street Center
201 S. Jackson St., Suite 500
Seattle, WA 98104-3855
Phone: 206-684-1280
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

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

Murray CSO control project

 Murray CSO basin project area
Murray CSO basin project area site plan (PDF, 1.3MB)
Source: Draft West Seattle CSO Control Facility Plan, December 2010

Project area

King County plans to design and build a one million gallon underground storage tank on private property across from Lowman Beach Park along Beach Drive S.W. This facility will store peak flows when the Murray Pump Station exceeds capacity. The recommended proposal also involves an underground diversion structure located under the southeastern corner of Lowman Beach Park and an ancillary equipment facility (odor and electrical unit) above ground on the storage tank site.

Project elements

The recommended proposal includes the following elements.

  • Property acquisition
  • An underground diversion structure located in Lowman Beach Park
  • A pipe connecting the diversion structure to the storage tank to convey peak flows during a wet weather event
  • An approximately 6,000 square foot underground storage tank across from Lowman Beach Park
  • Access hatches on the tank site for operations and maintenance activities
  • Retaining wall to protect the existing hillside along the northeast, east, and south edges of the storage tank site
  • One story equipment facility including odor control and electrical facilities, located above the storage tank 
  • Landscape restoration in Lowman Beach Park and above ground at the storage tank site

Learn more about the preferred proposal

Underground storage tank facility concept.
Underground storage tank facility concept (PDF).
This is a typical profile of an underground storage tank facility used for controlling flows in a wastewater conveyance system.

Looking South along Beach Drive Southwest at the intersection of Lincoln Park Way Southwest
King County plans to design and build an underground storage tank beneath private property (left) across the street from Seattle’s Lowman Beach Park (right).

How the Murray Storage Facility works to control CSOs
How the underground pipeline storage facility works to control CSOs (PDF)

Draft Facility Plan (December 2010)