Green Stormwater Infrastructure

Together, we can use Green Stormwater Infrastructure (GSI) to collect, slow, and treat rain once it hits the earth and becomes stormwater. This will reduce flooding, sewer overflows, and pollution entering our waterways. GSI can take many forms, from rain gardens to trees, and delivers multiple benefits to communities and cities.

What can you do with GSI?

Build a rain garden on your property through the RainWise Program
Build a small rain garden (PDF) or bioretention system (PDF) in the planter strip yourself (for bioretention that manages stormwater from a larger area, check out Regional Voluntary Bioretention in the Right-of-Way)
Plant a tree!
Learn how to maintain GSI in your neighborhood (PDF)
Learn more about GSI:
- GSI Progress Report (2021) (PDF)
- GSI Progress Report (2020) (PDF)
- GSI Progress Report (2019) (PDF)
- GSI Progress Report (2018) (PDF)

What is SPU doing with GSI?

Building and maintaining GSI projects through our capital program to keep Puget Sound clean
Collaborating with the Seattle Department of Construction and Inspections to enforce the Stormwater Code to ensure stormwater best management practices when parcels are redeveloped.
Developing partnerships that help weave GSI into the built environment. More information about these programs will be provided when available:
- RainWise is a City of Seattle and King County rebate program that helps eligible private property owners manage stormwater by installing cisterns and rain gardens.
- RainCity Partnerships Program partners with eligible multi-family, commercial, and industrial private property owners in selected neighborhoods to build voluntary green infrastructure projects and restore riparian areas to improve water quality and habitat waters.
- Beyond Code Partnerships support developer projects that have Stormwater Code minimum requirements and would benefit from a more holistic approach to stormwater management that can achieve greater impact above and beyond code requirements.

GSI Benefits

Cleans stormwater before it enters our creeks, lakes, and Puget Sound
Reduces combined sewer overflows into our living waterways by keeping stormwater out of the system
Reduces flooding in our neighborhoods
Provides welcoming and colorful gathering spaces for our communities
Improves air quality
Stores more carbon in the ground
Slows traffic

Types of GSI

Rain gardens
Rainwater reuse systems
Bioretention (also known as Natural Drainage Systems)
Biofiltration swales
Trees
Green roofs
Permeable pavement
stormwater ponds
Floodable open space
Reconnecting urban creeks to natural floodplains

Additional Resources

Contact Information

For additional information about Green Stormwater Infrastructure programs, please contact Tracy Tackett, Green Infrastructure Program Manager, at tracy.tackett@seattle.gov or (206) 386-0052.