Local

Floodwater caused extensive damage to West Point sewage plant

UPDATE: On Saturday, Feb. 18, officials said the entire plant is expected to be dry enough for inspections by Feb. 24.

SEATTLE — In a part of the West Point Treatment Plant called "the dungeon," pretty much everything is ruined.

A mix of stormwater and untreated sewage surged through the underground sections of the plant last week.

The nasty floodwater was 12 feet deep in the corridors.

In a boiler room, the water line is about 14 feet above the floor.

Two-hundred pump motors and 100 electrical panels need replacement.

King County officials estimate that thedamage is in the tens of millions of dollars.

The plant flooded during a rainstorm in the early morning hours of February 9, when, in the section of the plant that moves water out into Puget Sound, two pumps failed, and then a third shut down automatically.

The cause of the pump failure is still not known.

It happened as 15 million gallons of stormwater poured in.

"That is a tremendous amount of water," said Mark Isaacson, King County's wastewater division director.

At least 260 million untreated gallons diverted directly into Puget Sound; 10 to 15 percent of it was raw sewage.

A similar, smaller diversion happened during a rainfall this week.

The plant is now at half capacity, and the water that does run through is not being fully treated.

State regulators say the discharge into the Sound is disinfected, but cloudy, a violation of federal permits.

Isaacson said it could be weeks before the plant is fully operational again.