A wastewater operator sits facing away from us, in front of multiple computer screens that help monitor the treatment plant processes

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

Our crews are on the job 24/7, 365 days a year to ensure the region’s wastewater treatment service – and that remains true as we move into the rainy season. Workers are ready to respond around the clock and work hard to be well-prepared for stormy weather or an emergency. To make sure we’re ready…

Banner with a photo of Lake WA and Mt Rainier and text that says construction in Mercer Island & Bellevue to start early 2022

Major construction in Mercer Island & Bellevue to start early next year

Our relationship to water is what makes this region special.  King County is a partner in this relationship. Regional wastewater treatment plays a key role in keeping our rivers, lakes, streams, and the Puget Sound clean for people and aquatic life. We manage a big regional wastewater system that needs regular inspection, maintenance, and upgrades…

Puget Sound view from the SoundGuardian boat

Reducing nitrogen in Puget Sound where it matters

King County is committed to protecting water quality and reducing harm to fish and aquatic life in Puget Sound’s shallow bays caused by human sources of nitrogen. The Department of Natural Resources and Parks supports a science-based approach that capitalizes on innovation and technology and focuses public resources where they can make a real difference.…

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…

Delivery of sodium hypochlorite – a chlorine compound and disinfectant in common household bleach and the primary disinfectant used in our wastewater treatment process

Regional chlorine / sodium hypochlorite shortage: How we’re conserving to protect public health and the environment

What is happening A nationwide shortage of sodium hypochlorite – a chlorine compound and disinfectant in common household bleach and the primary disinfectant in our wastewater treatment process – triggered by a supply-chain disruption, is impacting wastewater treatment operations throughout the Northwest, including King County. Like several other utilities in the region, our staff is conserving the disinfectant while we try to…

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…