May 18, 2006
Grease-blocked sewer pipe causes overflow in Bellevue
City of Bellevue crews quickly responded last week to a local sewer
overflow that was later found to be caused by a grease blockage
in King County's Issaquah Interceptor. The interceptor is a large
sewer line that carries wastewater from homes and businesses in
the Issaquah and Bellevue areas to the county's regional wastewater
plant in Renton for treatment.
Between 5,000 and 15,000 gallons of wastewater overflowed from a
manhole near the intersection of S.E. 47th St. and 194th Ave. S.E.
into a nearby creek that flows to Lake Sammamish. City of Bellevue
staff stopped the leak, cleared the blockage, and began clean-up.
To protect public health, they posted a nearby beach as closed,
took water samples, and told health and regulatory agencies about
"City of Bellevue staff deserve recognition for their prompt, professional
response," said King County Wastewater Treatment Division Director
Don Theiler. "Even though it was later found to be our pipe, their
quick action kept the overflow from becoming a much bigger problem."
King County is working with City of Bellevue to understand how so
much grease could block such a large pipe so they can prevent it
from happening again.
Grease gets into the sewer system from household drains or businesses
with poorly maintained grease traps, where it sticks to the insides
of pipes. Over time, grease build-up can block an entire pipe and
cause sewage overflows.
"One of the best ways people can keep fats and grease out of the
sewer is to keep it out of their drains," said Theiler. "Not only
does it help prevent sewer system overflows, it can help people
avoid their own costly plumbing problems."
People can get more information about how to properly dispose of
fats, oils and grease, by visiting http://dnr.metrokc.gov/WTD/community/oldstuff.htm
or calling the Wastewater Treatment Division at 206-684-1280 or