In older parts of the King County sewage system, both rain water and sewage travel down the same pipes to the wastewater treatment plant. During heavy rains, these pipes often overflow sending the untreated water directly into Puget Sound. This is called Combined Sewer Overflow (CSO). One of the trouble spots is in the Magnolia area.
In 2008, King County reported that the South Magnolia CSO facility has 19 overflows per year on average that discharge a total of 31 million gallons into Puget Sound. Options being considered to resolve this issue must be capable of managing a volume of about 1.8 million gallons of peak flows in order to meet regulatory requirements.
The proposal above shows an underground storage tank located in the Seattle Parks property along 32nd Ave West. It would provide odor control and electrical facilities with an underground diversion structure to send flows to the tank. The city says that there are challenges with this plan, because of the steep slope location and the narrow street. Information about other proposed alternatives for CSO control projects in South Magnolia can be found here along with the pros and cons for each alternative.
There is a community meeting on Tuesday March 23 at the Magnolia Community Center from 6p.m. to 8:30 pm to discuss the alternatives. Until April 16, Magnolia residents can also fill out an online feedback survey. Public input will be used to determine what proposal the country will forward for environmental review. This spring, the project team will refine and review these alternatives. Fill out the form here and select feedback form in the header.
