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Sewer Overflow Reaches Duwamish, people advised to avoid water activities

UPDATE, September 22, 2019, 7:30am: Public Health Seattle-King County has reopened the Duwamish to water activities like fishing after test results confirmed acceptable levels.

September 20, 2019

(Seattle)- Seattle Public Utilities (SPU) has responded to a sewer overflow that reached the Duwamish River. SPU and Public Health-Seattle & King County (Public Health) are warning the public to refrain from water activities like fishing. Public Health’s current closure extends from the Turning Basin (just upstream from the Museum of Flight) to Harbor Island.

SPU received a report about 1 pm Thursday about suspected sewage in a ditch near King County International Airport-Boeing Field. SPU’s Spill Response team reached the site within 30 minutes to investigate the report and conduct testing. After results indicated a sewer overflow, SPU immediately relieved a blockage, caused by a lodged piece of plywood, in a City sanitary sewer line. SPU estimates the total overflow at 320,000 gallons.

SPU also contacted its regulators and partners, including Public Health, WA Dept. of Ecology, WA Dept. of Fish and Wildlife, City of Tukwila, King Co. Intl. Airport-Boeing Field and local tribes. 

SPU will continue sampling until results confirm acceptable levels.

Public Health recommends that people should avoid coming into contact with sewage-contaminated water. If you do get contaminated water on your skin, wash thoroughly with soap and warm water. Health impacts from exposure to sewage primarily include gastrointestinal illness and skin infection. While this sewage spill is being cleaned up, people may want to avoid eating fish from the river. Due to legacy chemical pollution, the lower Duwamish River has had an on-going fishing advisory that recommends only fishing for salmon. Always avoid bottom dwelling seafood species in the lower Duwamish.

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