Georgetown Wet Weather Treatment Station
Seattle
BEST PROJECT
Presented by Signal Architecture + Research
owner King County Wastewater Treatment Division
Leading design company The Miller Hull Partnership & Signal Architecture + Research
General Contractor Flatiron Dredged
Civil Engineer/MEP Jacobs; HDR
Structural Engineer Jacobs Engineering; HDR; Brilliant engineering
Lighting design White lighting
artist Sans Facon
Public Art 4 Culture
Community involvement Environmental problems
Rather than hiding behind fences, this wet-climate installation stands prominently at the gateway to the Georgetown neighborhood, leveraging the site’s strategic placement, architectural scale, and integrated public art to communicate its mission to improve the ecological health of the Duwamish River.
The Theater of a Storm, a sequence of light-based interventions, tracks each stage of treatment through the architectural forms of the installation, from intake to ultraviolet disinfection, making visible what would otherwise remain hidden.
Installing a highly technical treatment facility on only 2.5 operational hectares posed multiple challenges. The design team responded by stacking the buildings vertically, using gravity to move water through the system and dramatically reducing energy consumption, maintenance needs and physical footprint.
Lara Swimmer’s photo
Geotechnical improvements were also critical due to the high water table. Liquefaction-prone soils that turn into quicksand during earthquakes required soil reinforcement with stone columns to create solid support for the heavy processing buildings. A 35-foot-deep concrete slab anchored the 100-foot-deep, 100-foot-diameter underground equalization basin, resisting groundwater buoyancy. Crews installed sheet piles and desiccants before excavating through contaminated soils, sequencing earth retention structures and turbidity curtains to protect adjacent waterways.
Lara Swimmer’s photo
Treating up to 70 million gallons of combined stormwater and wastewater daily during approximately 20 storms per year, the project significantly reduces pollution in the Duwamish River. The project also achieved more than 85% waste diversion, reusing wood in interior finishes and recycling concrete for underground fill.
In recognition of its social, economic and environmental benefits, the project earned Washington State’s first Platinum Envision certification.
