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web banner: Be RainWise, rebates for rain gardens and cisterns, SPU and KC

RainWise Goes Virtual to Support Contractors - Learn more.

RainWise—Private property owners can be part of the stormwater pollution solution

With every storm, rain carries pollutants off our roofs, driveways and other hard surfaces to creeks, the Duwamish River, our lakes and Puget Sound. During big storms, the sheer volume of this “stormwater” can cause sewer overflows and polluted runoff.

RainWise helps private property owners install rain gardens and cisterns to help manage the rain that falls on their roofs. In addition to stopping water pollution, these installations can add attractive landscaping, provide water for summer irrigation, and may reduce flooding. 

To find out if you qualify for rebates, see examples of rain gardens and cisterns, and learn more about how to get RainWise, check out

How to become RainWise

RainWise rebates cover most or all of the cost of installing cisterns and rain gardens on private properties in eligible combined sewer overflow basins. The average rebate has been around $4,400.

Here is how you get started:

  • The first step is to check your eligibility at
  • The next step is to find a contractor. If you can't attend one of our online Contractor Meet Ups, email us at with the subject line "Contractor Matchmaking" and we will help you find the best contractor for your needs.

You can also:

For more information, visit the 700 Million Gallons website .

RainWise, by the numbers (through spring 2021)

Visit the 700 Million Gallons website for more information or go on a RainWise virtual garden tour  !

two people standing behind rainwise signage

rain garden

two people next to a cistern

woman in red coat with yellow umbrella next to rain wise garden

Janice Johnson
CSO Control Program