On-Call Green Stormwater Infrastructure (GSI) Services

The City of Seattle is seeking proposals for On-Call Green Stormwater Infrastructure (GSI) Services . Proposals are due no later than 1:00 pm on Thursday, July 31, 2025 . All questions are to be submitted through the e-procurement portal at https://procurement.opengov.com/portal/seattle no later than 1:00 pm on Tuesday, July 8, 2025 .

Seattle Public Utilities (SPU), in partnership with King County Wastewater Treatment Division, is soliciting proposals from Consultant Teams to provide consultant services to support the administration and development of Green Stormwater Infrastructure (GSI) and drainage capital projects, partnership programs, and policymaking. SPU will select one Consultant Team for a two (2) year On-Call contract term with the option to extend an additional three (3) years – five (5) years maximum.

GSI is SPU and King County’s preferred stormwater management approach because it reduces polluted runoff and flooding while delivering multiple benefits to the community. This contract requires strong project management and will provide programmatic support in areas like regulatory and policy compliance, engineering and design (green and green/grey), data analysis, workforce development, training, and community engagement.

The term “green stormwater infrastructure” encompasses infrastructure that preserves, enhances, or mimics natural infiltration, evapotranspiration, or capture of stormwater as a method of achieving our stormwater goals. GSI is used across multiple scales and site contexts—including residential, commercial, and in the public right-of-way—and delivers multiple community benefits in addition to stormwater management. SPU values GSI as a cost-effective way to improve our drainage and wastewater systems. The GSI toolbox includes, but is not limited to, bioretention, rain gardens, permeable pavement, vegetated roofs, rainwater harvesting, multifunctional stormwater ponds, nature-based sea level rise protection strategies and creek floodplains.

Through this work, the selected Consultant Team will provide essential, equitable services to help meet each utility’s strategic business plan goals ( https://www.seattle.gov/utilities/about/plans/strategic-business-plan ) and regulatory commitments while contributing to long-term outcomes including healthier water for people and fish, greater climate resilience, access to nearby nature, and stronger, more connected communities. This program is also anticipated to incorporate SPU’s 1% for Art Program.

You can find background information on prior GSI efforts can be found at the following locations:

• 700milliongallons.org , includes prior annual progress reports
• SPU GSI website: Seattle.gov/utilities/your-services/sewer-and-drainage/green-stormwater-infrastructure