About King County Wastewater Treatment Division

WTD is an innovative clean water utility that provides wholesale wastewater treatment services to nearly 2 million people across 34 local jurisdictions and sewer agencies in the Puget Sound region in Western Washington. 

We are dedicated to our mission to protect public health and the environment by collecting and cleaning wastewater while recovering valuable resources for a thriving Puget Sound region. 

The Division’s 700-plus employees manage and operate the regional system of treatment plants, pipelines, and pump stations that provide an essential service 24/7. We also plan and design new facilities, regulate the disposal of industrial waste, and educate the public on pollution prevention.

By exploring new technologies and harnessing valuable resources from the treatment process — such as biogas energy, recycled water for irrigation, and biosolids to return carbon and nutrients to soils — WTD supports sustainable communities. 

More information and facts about our system is available here.