Miller Hull

Georgetown Wet Weather Treatment Station

Seattle, Washington
Process as theater
Client King County
Size 133,500 SF (site) | 26,649 SF (building)
Completion 2022
EMission Zero Offset 176 tCO2e


While population has grown rapidly, King County sewers have remained the same size, causing them to overflow during heavy rainfall. Currently under construction with an expected completion date in 2022, the Georgetown Wet Weather Treatment Station (GWWTS) facility will provide up to 70 million gallons per day (MGD) of secondary treatment capacity during wet weather events, diverting flows that would normally discharge untreated wastewater into local waterways when the conveyance system is overloaded.

The GWWTS facility is a campus composed of infrastructural buildings as well as an Operations and Maintenance Support building that will serve as a more public frontage of the facility. The Operations and Maintenance Support Building at the most visible corner of the site provides a strong and welcoming public identity for the facility, incorporating a training room that is can accommodate a variety of community events. King County, in partnership with local community colleges, will develop and lead interpretive programs accessible to local schoolchildren and community members to build awareness surrounding the importance of this facility and inspire active stewardship of one of our most important natural resources.

Project Team

Design Collaborator & Architect of Record: The Miller Hull Partnership, LLP
Design Collaborator: Signal Architecture + Research
Engineer: Jacobs Engineering Group
Contractor: Flatiron Construction
Landscape: Berger Partnership
MEP Engineering & Structural: HDR
Lighting: Blanca Lighting Design

EMission Zero Offset

In 2021, Miller Hull offset 16,679 tCO2e (tons of carbon) of seven projects as part of our recently launched EMission Zero initiative — a program announced in 2021 targeting the elimination of greenhouse gas emissions in the built environment. A major component of EMission Zero is Miller Hull’s commitment to voluntarily purchase Green-E certified carbon offsets to cover the embodied emissions of each built project upon completion.