Murray CSO control project -- Building a new storage tank to protect Puget Sound
December 12, 2014 Update
King County contractors are beginning to build the underground storage tank. The tank will sit on top of the concrete slab poured in tank area over the last week. Crews will work Saturday Dec. 20 to install rebar and build forms. The rebar will attach the tank to the slab. The forms will help shape the tank bottom. Saturday work hours will be 9 a.m. to 6 p.m.
Smaller concrete pours are scheduled for December 23 and December 29. About 10 trucks an hour will deliver concrete to the site each day — less than half the amount delivered daily for the slab. Concrete will be delivered to the site between 7 a.m. and 6 p.m. Crews may continue working in the tank area after 6 p.m. if necessary. Haul routes will remain the same. These pours may be rescheduled if temperatures go below 40 degrees. Schedules updates will be provided as necessary.
No work will occur on December 25 or January 1.
Learn more: view the construction update (PDF, December 12, 2014).
Have a comment or question? Need more information about the project?
Click here to contact the project team.
Murray Project Hotline: 206-205-9186
Final Design, December 2012
Project haul routes, February 2014
Murray basin and project location
King County is designing an underground storage tank across the street from Seattle’s Lowman Beach Park. The tank will store approximately one million gallons when the Murray Pump Station exceeds maximum capacity.
Why do we need this project?
Protect public health
Like many cities around the country (external link), the older parts of King County's wastewater system uses a single set of pipes to carry untreated sewage and stormwater to a treatment plant. To prevent sewer backups into homes and streets, the system includes safety valves called “combined sewer overflows” that route excess sewage and polluted stormwater flow directly into Puget Sound during storms. Although CSOs reduce potential exposure to untreated sewage, they pose significant public health concerns.
Clean up Puget Sound
The Murray CSO control facility will reduce CSOs 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.
View construction schedule overview (PDF) and project meeting calendar.
How has the community shaped facility design?
Since October 2011 Lowman Beach Park neighbors and park users have worked with local designers, environmentalists and community advocates to help the King County project team design a facility that fits with the community. These discussions produced “common themes” for the design that reflect the community’s values for a safe, reliable facility. The common themes are:
- Minimize the “industrial facility” feel
- Encourage views of Puget Sound
- Discourage through traffic on Beach Drive
- Enhance continuous space between Lowman Beach park and the facility site