Green roof at Sunset Pump Station

Making projects sustainable, resilient, and equitable

King County’s Wastewater Treatment Division (WTD) is being recognized for its commitment to sustainable communities and the environment. WTD’s Sunset / Heathfield Pump Stations and force main upgrade project was awarded an Envision® Silver Award this month for project sustainability. This is the second Envision-certified project for the region’s wastewater utility. In 2018, King County’s…

Aerial view of the West Point Treatment Plant

Charging ahead with reliable battery power for West Point Treatment Plant

The West Point Treatment Plant processes about 100 million gallons of wastewater each day, and up to 440 million gallons during heavy rains. While the plant’s operators are working hard to keep the treatment process flowing smoothly, a momentary lapse of power supply quality can bring vital equipment operations to a hard stop.   That’s why in February 2021, King County Executive Dow Constantine signed an emergency declaration and the King County Council authorized up to $65 million to provide West Point with more reliable power. The team…

Construction of a wastewater facility

Wastewater employees’ thoughtful approach earns industry award

Our employees plan, design, build, and operate treatment facilities to clean wastewater for the region. Planning and building new wastewater infrastructure is complex. It can easily take a decade or more to go from identifying a project is needed, to cutting the ribbon on a newly completed facility. Each project goes through several phases of…

Odor control equipment

What’s that smell? Controlling & reporting odors

It’s important to us that our wastewater facilities to be a good neighbor to the people who live, work and play near them. Part of being a good neighbor means that we work hard to control odors / smells that come from the wastewater treatment process—which can get gassy! Why does sewage smell? Treating dirty water at…

Starting a decade of improvements at West Point Treatment Plant

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 it’s components reach their “end of life” each…

collage of all the images in this slideshow

UPDATED: We’re working to improve power supply quality at West Point Treatment Plant to continue our clean-water mission

Power disruptions during heavy rainfall As a clean water agency, our mission is to protect public health and the environment. We work 24/7 to serve over 1.8 million residents and clean about 190 million gallons of water per day. Even in massive rainstorms that generate more volume than the system can handle, we feel any…

Lake Sammamish

Working with Sammamish Plateau: No regional capacity limits and Diversion Project moving ahead

We clean wastewater for the region Pipes from homes and businesses in this area connect to local sewer systems. Then those local utility pipes connect to our bigger pipes, which carry wastewater to one of our regional treatment plants where we clean it. The local agencies own and operate their independent collection systems. The local…

Wastewater workers prepare for rainy weather

As rainy weather approaches, we are on the job 24/7

As we move into the rainy season, our crews are on the job 24/7 to ensure the region’s wastewater treatment service is well-prepared for an emergency or stormy weather. To make sure we’re ready for what wet weather can bring, we have inspected and replaced equipment, updated control systems and increased training of treatment plant…