Officials are investigating after failures at sewage treatment plants in Seattle have led to the spill of an estimated 3 million gallons of untreated sewage into Puget Sound.
The Department of Ecology confirmed that a combination of “power disruptions” and the failure of the backup pumping systems at the West Point Wastewater Treatment Plant in Seattle led to the spillage of around 3 million gallons of waste into Puget Sound, prompting the closure of several beaches due to bacteria levels in the water.
Officials said in a statement that the waste was “untreated” and the massive flow took place in just 27 minutes.
In King County alone, nine beaches were initially shut down and residents were urged to avoid water contact until further notice. An update Friday afternoon revised the list to just two beaches in the county.
Jefferson County issued a warning for Fort Worden State Park “due to high levels of fecal bacteria in the water.”
Kitsap County closed three beaches to water contact, as modeling showed sewage would likely reach the beaches.
While it is not clear what caused the backup pump systems to fail, the initial power disruption at the plant was caused by a Seattle City Light power surge and outage, King County officials said. More than 10,000 people were affected by the blackout.
According to Seattle City Light, more than half of the disruptions at the plant over the last 17 years were caused by “malfunctioning electrical facilities.”
Washington’s Department of Ecology is investigating the incident as “unauthorized discharges” that violate the state’s water quality permits.
“Ecology anticipates taking necessary enforcement actions after its full investigation.”
A similar power failure occurred Thursday at the Renton Wastewater Treatment Plant in King County for around 50 minutes.