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Brightwater Water Treatment Facility - Media ©Photography by Benjamin Benschneider © Photography by Benjamin Benschneider

Brightwater Wastewater Treatment Plant


King County’s Brightwater Treatment Plant (Brightwater) treats, on average, 36 million gallons of wastewater and produces seven million gallons of Class A reclaimed water each day for off-site uses, increasing to 21 million gallons per day based on demand. Brightwater uses state of the art membrane filtration to provide enhanced water quality for our region.

Mithun led a diverse team of consultants working with the community and the county on the design of the region’s new wastewater treatment facility. Protecting public health, the environment and wildlife — including salmon — was a major goal for the project. The team looked beyond the Brightwater site to ensure that the plant and LEED® Platinum Brightwater Center fit within the region’s development patterns and natural systems. Throughout the plant, buildings are integrated into the landscape to communicate the nature of the site and to welcome the public to walk the hills along an education trail. The design of the treatment plant maximizes efficiency and facilitates maintenance and operation activities. A shared language of building features creates design unity and supports a positive working environment while meeting the technical requirements of the facility.

Mithun collaborated with artists Ellen Sollod, Jann Rosen-Queralt and Buster Simpson on an Art Master Plan for Brightwater that created thematic zones for integrating public artwork into the buildings, the treatment plant and the landscape. This project was also in collaboration with CH2M Hill, Brown and Caldwell, Hargreaves Associates, and Streeter and Associates.




Northwest Construction Consumer Council – Green Project of the Year

AIA Seattle What Makes It Green – Top 10 Green Projects in the Puget Sound


King County Wastewater Treatment Department


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