About 18,000 gallons of sewage spilled into Lake Washington late Saturday, closing a Seattle beach to swimming and boating.
The spill was caused by a blockage in a sewer main near Matthews Beach, according to a statement from Seattle Public Utilities spokesperson Cody Bowman. Seattle Public Utilities stopped the overflow around 11:22 p.m.
People and pets were advised to avoid the lake at Matthews Beach Park through Oct. 3.
An Olympic swimming pool is about 660,000 gallons, or about 36 times the size of the spill.
Samantha Washburn manager of Magnuson Cafe & Brewery near the park, said Sunday was a slow day, despite sunny weather.
“The only reason we found out about the spillage was because we have regulars who go swimming out on the lake, and they told us about it,” she said.
Public utilities crews will collect samples and provide updates on the lake’s condition, Bowman said in a statement. According to King County, routine sampling for bacteria at lake beaches stopped around Labor Day and will start again in May.
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