Sewage overflows into river

Equipment failure at the Coeur d’Alene wastewater treatment plant sent 130,000 gallons of raw sewage flowing into the Spokane River between 7 p.m. Friday and 2 a.m. Saturday, said Sid Fredrickson, the city’s wastewater superintendent.

Not only did the pump fail, but so did two separate alarm systems, Fredrickson said.

“We’re confident the raw sewage had dissipated by dawn,” he said. “It’s not a huge amount of spill, but any amount over zero is unacceptable.”

The storm sewer dumped the sewage directly into the Spokane River, just as it would rain or snowmelt. The drain pipe is not far from the wastewater treatment plant at 915 Hubbard Ave. The Spokane River flows out of Lake Coeur d’Alene and flows through Post Falls and downtown Spokane.

Officials are still investigating why the pump and alarms failed, Fredrickson said. Once the pump stopped working, sewage flowing into the plant began filling a large holding reservoir. A backup pump could not handle the incoming flow and the sewage began flowing up out of a floor drain in the wastewater treatment plant’s garage. The sewage then flowed overland until it reached a storm drain.

Although equipment failure is not unusual, alarm failure is “really rare,” said Don Keil, assistant plant superintendent. The alarm is meant to automatically call a plant operator when it senses trouble.

State officials took samples of the water below the storm drain outflow Saturday morning. Test results should be available within five days, Keil said.

Fredrickson said the risk to swimmers and boaters from the sewage was minimal.

On May 10, an accident at the Spokane sewer plant killed a plant worker and sent an estimated 200,000 gallons of sewage into the Spokane River.