The Goal

Why 700 Million Gallons?

As we replace forests and natural areas with buildings, streets, and yards, we still need to manage the runoff from rain, storms, and snowmelt. We can accomplish this by taking cues from nature itself, using green stormwater infrastructure (GSI) to clean runoff before it arrives in our wastewater system and waterways. Our goal is to use GSI to manage 700 million gallons of polluted water each year by 2025.

Keep reading to find out how you can partner with us towards this goal! Together, we can improve the health of our communities.


How are we doing?

Seattle is making great strides toward our goal to naturally manage 700 million gallons of stormwater annually by 2025. We are currently managing 710 million gallons annually!

Green stormwater infrastructure helps make our roads, rooftops and other hard surfaces work more like the forests and natural areas we have lost over time.

Learn more about the progress made in the 2023 year-end accomplishment highlights.

Progress through 2024 Q1


Partnerships for Greater Impact

GSI Around You

Hundreds of GSI projects have been built in Seattle over the past two decades. Click on this map to see each project organized by type, goal, and who built it.

Click on a dot to see more information about the project. You can learn more about current City of Seattle projects here and completed projects here.  Learn about current King County projects here.