Seattle and King County Fined for Sewer Overflow Violations

SEATTLE – The Washington Department of Ecology and the U.S. Environmental Protection Agency (EPA) are jointly issuing fines to Seattle and King County for violating conditions of their federal consent decrees and state water quality permits that regulate combined sewer overflows from parts of the sanitary sewer systems that serve Seattle residents and businesses.  

The fines are for violations that occurred between July 2020 and June 2021. Seattle’s penalty is a total of $117,500: $87,500 for 35 sanitary sewer overflow events and $30,000 for four dry weather overflows from combined sewer overflow discharge pipes (outfalls). King County’s penalty totals $53,500: $36,000 for exceeding pollutant limits at its wet weather treatment stations that treat combined sewer overflow discharges and $17,500 for seven sanitary sewer overflows.

Untreated or insufficiently treated discharges of sewage contain bacteria and other pollutants that can make conditions unsafe for people and animals. Combined sewers carry both stormwater and sewage. The city and county own and operate different parts of the combined sewer infrastructure within the Seattle city limits. Combined sewers were originally built with overflow points intended to discharge during large storms. State and federal law requires communities to eliminate these overflows except in extreme weather circumstances to minimize untreated sewage reaching rivers, lakes and Puget Sound.

Seattle discharges

Ecology and EPA are fining the City of Seattle $87,500 for 35 sanitary sewer overflow events. Sanitary sewer overflows are not allowed by the city’s discharge permit regardless of the type of weather. Several of the events reached Puget Sound, Elliott Bay, Lake Union, or the Duwamish River. A number of events resulted in sewage backing up into homes or other buildings.

Ecology and EPA are also fining the city $30,000 for four dry weather overflows from combined sewer outfalls. One discharged to Lake Washington, one to Lake Union, and two to Puget Sound. The city’s discharge permit does not allow discharges from combined sewer outfalls during dry weather periods.

King County discharges

Ecology and EPA are fining King County $36,000 for discharges from its Elliott West, Carkeek, and MLK/Henderson combined sewer overflow treatment facilities. The three facilities did not meet performance standards for removing solids that carry pollutants into the water. In addition, Elliott West had three discharges that exceeded limits for chlorine, a chemical that is toxic to aquatic life.

Ecology and EPA are also fining the county $17,500 for seven sewer overflows. Five of the events resulted from mechanical or electrical problems at pump stations operated by the county, which caused the release of more than two million gallons of untreated sewage to Lake Washington, Puget Sound, and the Duwamish River. Two events resulted in sewage backing up into homes. 

These violations do not involve King County’s main wastewater treatment plants—Brightwater, South Plant, and West Point.