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Starting a decade of improvements at West Point Treatment Plant

By May 5, 2021June 15th, 2023No Comments

Built in 1966, West Point Treatment Plant is the largest wastewater treatment plant by volume in Washington state, and the third largest by average daily flow on the West Coast. Like much of the King County wastewater system, it’s more than 55 years old and many of its components reach their “end of life” each year.

Over the next 10 years, we will  invest more than $660 million at West Point Treatment Plant in projects that will replace pumps and pipes, retrofit facilities for earthquake resiliency and improve the power supply. These capital improvement and asset management projects at West Point focus on protecting worker and public safety, and the environment, while protecting ratepayer investments through improving system reliability, and increasing efficiency.

  • West Point Treatment Plant
  • West Point in 1966.
  • Pumps
  • West Point tanks
  • Constructing the new screening building at West Point
  • Screening building construction
  • workers planting trees
  • CoGen power controls

This will be in addition the significant improvements we’ve made over the past four years at West Point to make it more resilient to storms and power fluctuations, including enhanced staff training, new electrical, alarm and control systems, adding redundancy at pump stations and making the equipment less sensitive to power fluctuations, but there’s more to do.

The projects to replace, repair and upgrade the equipment and facilities at West Point will help us continue to protect public health and the environment, serve more than 700,000 residents and treat 100 million gallons of wastewater per day.

We look forward to continuing our conversation with our community and neighbors about all of the upcoming projects at West Point. We welcome your feedback and will provide regular updates about our progress.

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