Learn about GSI Solutions

Installing nature-based drainage solutions on both public and private property helps Seattle to be a sustainable and resilient city.

Unlike pipes and treatment plants that collect and clean polluted runoff after it travels for miles, GSI uses plants, trees, soil, and engineering inspired by natural drainage systems to manage stormwater where it falls. By mimicking natural processes, we protect our waterways AND enjoy numerous other benefits. Green Stormwater Infrastructure increases the number of trees and plants in our neighborhoods, provides habitat for pollinators, improves air quality, and naturally replenishes groundwater.

Increasing the reach and effectiveness of GSI through technical innovation is a long-standing practice. Learn more about the history of GSI in Seattle, and what’s next for innovative GSI solutions.

Grants or other incentives are available for communities

King County and SPU offer a variety of resources and incentives for community projects ranging from donations of trees to sizable grants.

  • RainWise offers rebates for private property owners in certain CSO basins within Seattle. Find out more about that program and check your eligibility.
  • The RainScapes program partners with home and business owners in unincorporated King County to fund and install GSI features like rain gardens, cisterns, and native plant landscaping, on their property. Find out about that program and connect with program staff at their website.
  • Green Stormwater Infrastructure Mini Grants provide up to $1,500 for landowners within the King County Wastewater Treatment Division (WTD) service area that are not eligible for other incentive programs. Up to $4,500 may be provided to income-limited landowners.
  • Outside of King County and ready to invest in green infrastructure on your property?  The 12,000 Rain Gardens website has a list of regional incentive programs.
  • King County’s Waterworks Grant Program provides funding to organizations for projects that improve water quality in the service area for King County’s regional wastewater system.
  • Seattle grant opportunities can be found in this community guide to partnership opportunities.
Looking for resources to help fund your project?
Grants and other incentives are available.