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West Point Treatment Plant restoration update for Thursday, March 9, 2017


Restoration activities are continuing around the clock at the King County West Point Treatment Plant, where workers are on schedule to have full wastewater treatment capabilities back online by April 30.


Crews working seven days a week remain on track for restoring full wastewater treatment function at the West Point Treatment Plant by April 30 following an equipment failure in February that reduced the facility’s wastewater treatment capabilities.

No emergency bypasses of highly diluted stormwater and wastewater into Puget Sound have occurred since Feb. 16 at the plant, which has capacity to provide limited wastewater treatment for up to 250 million gallons per day. This capacity is nearly double the amount needed to treat an average day this time of year, but well below the plant’s designed capacity of 450 million gallons per day.

Wastewater treatment is continuing at the plant, including screening, some solids settling and disinfection. Treated wastewater is being discharged through the plant’s deepwater outfall, which is roughly three-quarters of a mile offshore on the bottom of Puget Sound where currents provide continuous dilution.

Progress report for March 9:
About 70 employees and contractors are at West Point today, March 9, and they are working on a variety of projects along King County’s critical path for wastewater treatment restoration.

• Crews have removed about 90 percent of the damaged insulation that protects the extensive network of heated pipes, which are essential to restoring secondary wastewater treatment at the plant. One of the plant’s boiler systems has been refurbished and is expected to be up and running by the end of next week.

Bringing this boiler system back online is the second major milestone along the critical path for restoration; the first milestone – completing major cleanup operations throughout the plant and preparing the primary system for full function – was achieved on Feb. 28.

• Crews have also installed a temporary boiler system that has been brought in is being wired this week and available for use as a back-up system beginning next week.

• Elsewhere in the plant, workers have been replacing electrical switches and instrumentation panels that were damaged as a result of the Feb. 9 equipment failure and flood.

New electrical panels are expected to arrive at the plant next week, and they will be installed as soon as possible. Replacement motor control cabinets have been designed and ordered, and they will be installed as soon as they arrive at the treatment plant.

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

Treatment plant operators are carefully monitoring weather reports and will watch rainfall totals.

If the volume of stormwater and wastewater flowing into the plant appears to approach the upper limit of the plant’s current treatment capacity, plant operators will divert a portion of the flow coming to other wastewater treatment facilities and avoid an emergency bypass into Puget Sound.

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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