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West Point Treatment Plant restoration update for Thursday, April 6, 2017


Workers at King County’s West Point Treatment Plant continue to be on schedule for restoring the wastewater treatment processes by April 30.


Steady progress is being made toward restoring the wastewater treatment processes at the West Point Treatment Plant by April 30, following the Feb. 9 equipment failure that limited the facility’s wastewater treatment capabilities.

All equipment that is critical to bringing West Point up to full wastewater treatment capability is operational and now the focus is on getting the biological processes back on line.

No emergency bypasses of highly diluted stormwater and wastewater from the plant have occurred since Feb. 16, and beaches that were temporarily closed immediately following emergency bypasses have been open since Feb. 21.

Wastewater treatment quality and capacity are improving at West Point. Treatment includes screening, primary treatment (grit, solids and scum removal) and disinfection. Added treatment capacity has cut in half the volume of solids discharged through the plant’s deepwater outfall into Puget Sound.

As part of West Point’s restoration, King County will temporarily increase truck traffic from the plant to haul primary sludge and biosolids. Up to 13 solids trucks spread out over a 24-hour period could be expected during the next seven to 10 days.

Progress report for Thursday, April 6:
King County employees and contractors are working on a variety of projects at West Point this week:

• Work to restore healthy biology to the secondary treatment systems continues to be the bulk of the remaining work. Crews have brought four anaerobic digesters online and up to their operating temperature, with a fifth digester expected to come online by mid-April.
• Workers are carefully feeding the sludge from the primary treatment process to the microorganisms that are at the core of the anaerobic digestion process by breaking down the organic solids that remain following the primary treatment process.

• Thanks to successful growth of the microorganisms in the secondary process, plant operators can now send about 60 million gallons per day of primary treatment effluent into the secondary treatment process.

• Equipment repair and replacement projects continue, including electrical panel installations, which are being done as soon as new panels arrive at the plant.

Upcoming weather:
During heavy rainstorms when the volume of stormwater and wastewater flowing into the plant appears to approach the upper limit of its current treatment capacity, plant operators can avoid an emergency bypass by diverting some of the flow headed toward West Point to other wastewater treatment facilities.

Keep up to date:
Stay informed about restoration work at the West Point Treatment plant. Visit the incident response page, and sign up for email updates, and follow on social media:

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