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West Point Treatment Plant restoration update for Thursday, March 30, 2017


Crews working around the clock remain on schedule for returning the King County West Point Treatment Plant to full wastewater treatment capabilities by April 30.


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

Wastewater treatment is improving at West Point, and now 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.

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.

Progress report for Thursday, March 30:
King County employees and contractors are working on a variety of projects at West Point this week, as they keep the plant on schedule for restoring full wastewater treatment capacity at the facility by April 30:

• Power has been restored to all of the plant’s equipment that is necessary to meet the April 30 deadline of full wastewater treatment operations. Any equipment that is currently running on temporary power sources will be converted to permanent power sources after full treatment capacity has been restored.

• Steady progress is being made in equipment repair and replacement projects, including replacing pipe insulation that is essential to the secondary treatment process, and replacing damaged electrical panels.

• Work to restore healthy biology to the secondary treatment systems has taken center stage. Crews have brought four anaerobic digesters online, and workers are slowly feeding sludge from the primary treatment tanks into the digesters, where a host of microorganisms break down the organic solids that remain following the primary treatment process.

• Thanks to increased restoration of primary treatment processes over the past several days, approximately 30 million gallons a day are being sent into the secondary process to gradually restore the health of the biological process.

• West Point is also now producing about two semi-truck loads of processed biosolids per day. LOOP is an organic, nutrient-rich soil amendment that is used in both commercial and residential agriculture applications.

Upcoming weather:
Rainfall in Seattle totaling one inch or more over two or three consecutive days could lead to an emergency bypass at the West Point plant of wastewater highly diluted by stormwater.

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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