skip to main content

Wastewater Treatment

King County, Washington

For questions about the Wastewater Treatment Division website, please send an e-mail message or contact us at:

King Street Center
201 S. Jackson St., Suite 500
Seattle, WA 98104-3855
Phone: 206-477-5371
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

Get Directions to our office location in Seattle, Washington.

Staff Contacts

Wastewater Treatment Division

King County, Washington, protects water quality and prevents water pollution by providing wastewater treatment to 17 cities and 17 local sewer utilities. The county's Wastewater Treatment Division serves about 1.5 million people, including most urban areas of King County and parts of south Snohomish County and northeast Pierce County. More about our system and facilities.

Learn how King County Wastewater Treatment Division creates safe underground
work environments using a construction technique called secant piles.

Reporting and viewing problems

Doing business with WTD

Learning about projects (under construction or in planning)

Getting involved in protecting the environment--citizen action


Check out WTD's new blog!
Check out King County WTD’s new blog!
The blog features stories about the work we do, including highlights on pollution prevention, our construction projects, and employee news.

Start your RainWise project today! Get ready for spring!
Start your RainWise project today! Get ready for spring (external link)! The RainWise program provides rebates that cover most or all of the cost of installing cisterns and rain gardens on your property. To receive a rebate, you must live in an eligible combined sewer overflow basin. Learn more (external link).
Jobs for Clean Water
What do you know about jobs related to clean water and sanitation? Watch these short videos and learn about the role of laboratory specialists, operations staff, and maintenance staff in protecting human health and the environment every day.
West Point Treatment Plant tour
View a tour of the West Point Treatment Plant.

Loop -- turn your dirt around
Turn your dirt around. Learn more about Loop.