Seattle, King County to pay for sewage flow into local waters

The City of Seattle and King County have been cited for discharging sewage into local bodies of water beyond allowable limits.

The Department of Ecology has fined King County $63,500 and the City of Seattle $33,500. Ecology essentially found that the city and county discharged sewage into neighboring bodies of water beyond what is allowed.

>>Video: Is that sewage churning in Elliott Bay?

“The county and the city are taking these violations seriously and they are making good progress on their CSO control programs,” said Mark Henley with the Department of Ecology. “They just need to do a little bit better to not violate their permit.”

King County was cited for 23 violations, and Seattle was cited for 10 violations. All incidents happened throughout 2015. Ecology found that King County exceeded pollutant limits from its treatment plants 18 times. Ecology also notes that two out of the four county treatment plants were found in violation of solids removal limits.

“(The county) is mostly regarding one of their CSO satellite treatment plants, called Elliott West,” Henley said. “That’s for various pollutants above the allowable limits, which includes fecal coliform bacteria and excessive levels of chlorine in their discharge.”

Fecal coliform bacteria is basically what it sounds like — scientifically speaking, it originates in the intestines of warm-blooded animals. But locally, excessive levels of the fecal bacteria made it through the sewage lines, and eventually flowed into places like Lake Union and Lake Washington.

Seattle had a similar case. Ecology discovered that the city allowed two unpermitted overflows from its outfalls during dry weather, and seven preventable overflows during other times.

This all means that sewage overflowed into Puget Sound, Elliott Bay, Lake Washington, Lake Union and Longfellow Creek.

How does sewage get into local waters?

The city and the county have federal consent agreements with Ecology to limit how often combined sewage overflows enter local waters. It’s part of the Clean Water Act. And it’s also part of a lawsuit settlement after the agencies violated the act in the past.

What is a combined sewage overflow? The region’s wastewater systems are a bit old and were built for a much smaller population decades ago. Stormwater and sewage — everything that flushes from your home or office building — combines into one pipe and heads to a wastewater treatment plant.

But since it rains quite often and heavily in the Pacific Northwest, those combined pipes tend to fill up fast. When that happens, the pipes overflow into the nearest bodies of water, sending sewage into Lake Union, Elliott Bay, Lake Washington, Puget Sound, etc.

Sometimes local agencies can treat that overflow before it gets to the water. But often it goes into the waters untreated.