A malfunction at a pump station sent about 11,000 gallons of sewage into the Willamette River, according to the Portland Bureau of Environmental Services.
The sewage discharges happened Sunday night and Monday morning from a pump station near the Morrison Bridge. The amount of sewage released is so small that it’s “practically undetectable,” Bureau spokeswoman Diane Dulken said. She added that the discharge is also much lower than storm-related sewer overflows.
“We never want to see any sewage in the river, but in terms of the volume we treat or the volume of the river, it’s relatively low,” she said.
The city treats an average of 70 million gallons of wastewater every day at its two treatment plants.
Even though the amount of sewage released isn’t large, city officials advise people to avoid contact with the river’s water between the Morrison and Fremont bridges for 48 hours – and to keep their dogs out of the water as well.
It’s not known what caused the pump-station malfunction, Dulken said. There are 99 pump stations in the city. They collect, lift and transport wastewater or sewage when it cannot be carried by gravity.
