The county department that runs West Point wastewater-treatment plant already did a preliminary investigation of the Feb. 9 disaster, but the council launched an additional, independent look into exactly what happened.

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A disastrous flood at the West Point wastewater-treatment plant will be getting an independent, third-party review, the Metropolitan King County Council decided Monday.

The review, approved on a unanimous vote, is intended to look at what occurred in the lead-up to and aftermath of the Feb. 9 flood that destroyed half the plant.

The region’s largest plant is operating at only partial capacity after the flood destroyed more than 500 pieces of equipment. The entire secondary treatment plant is sidelined, while the primary treatment plant and solids-management equipment at the plant are repaired and put back in service.


Members of the public who are interested in learning more can come to a community meeting Saturday being convened by Councilmember Jeanne Kohl-Welles. The meeting will start at 10 a.m. and will be held at the Episcopal Church of the Ascension in Magnolia, at 2330 Viewmont Way West in Magnolia Village.

Source: Metropolitan King County Council

Meanwhile the plant’s treatment capacity is greatly diminished. The plant is releasing wastewater into Puget Sound not nearly as clean as its state permit requires. And the plant can treat only half its usual volume.

West Point treatment plant

‘Lucky no one died’: What caused the catastrophic flood at West Point


In very high water events, plant operators must resort to its emergency bypass of sewage and stormwater to Puget Sound with no treatment at all.

The King County Wastewater Treatment division already has come out with its preliminary assessment of what caused the flood,implicating equipment failures but ruling out any employee mistakes. The division also called for a third-party, independent investigation. But the division canceled that effort Monday, given the council’s review.

The council wants to do its own review, so the questions and assessment of the report are not taken up by the same branch of government that runs the plant, council members explained.

“I believe very strongly what is needed is a wide-ranging, fully independent investigation not only of what occurred during the event, but in the lead-up and the aftermath of the West Point catastrophe,” said Councilmember Jeanne Kohl-Welles. “This must be totally transparent and totally independent.”

In addition to the damage, the report is to assess how the flooding could have been averted and a review of the environmental and public-health impacts of the flood and damage to the plant, as well as a review of prior events and lessons learned.

The council will lead its review and report the findings. “We need a full and unbiased understanding of what went wrong … and what will be done to be sure this type of catastrophe never happens again,” Kohl-Welles said.

Co-sponsors were Councilmembers Kathy Lambert and Rod Dembowski.

“It’s not usually one cause,” Dembowski said. “It’s usually a number of things … whether mechanical, or management, or both.”

The scope of the review is intended to help gather the widest picture of what happened.

The report will be due back by July 1. The contractor will be selected by the council’s chief of staff.

Meanwhile, work continues at the plant to get it back in normal working order.

The first task is restoring heat to digesters that manage solids at the plant. Beneficial microorganisms within the digester tanks have been largely without heat or food since the flood. They can’t work properly without an environment largely like your own gut at 98.6 degrees and with a regular stream of food.

The rest of the plant can’t be back up online until the digesters are working right, because there has to be a place to put the solids processed by the plant.

Full startup of the digesters is scheduled for April 24, and restart of the plant on April 30. But that schedule could slip if the delicate ecosystem of secondary treatment, including the digesters, is upset and requires a start-over.

Christie True, director of the King County Department of Natural Resources and Parks, which has authority over the wastewater-treatment division, said her department supports the council’s review.

“Both the Department of Natural Resources and Parks and the Council recognize the importance of a comprehensive independent expert review,” True said in a prepared statement. “The Department is committed to working collaboratively with the Council and the consultant.”