When water from rain or snow flows over the ground and cannot soak into the land it is called stormwater runoff. Runoff increases when rain falls on surfaces the water cannot penetrate, called impervious surfaces. The runoff is typically collected in ditches, inlets, and pipes and is released to larger bodies of water such as streams, ponds, lakes, wetlands or the Sound.

An impervious surface is non-porus and does not allow water to soak through the surface. Examples include: roofs, sidewalks, driveways, and roadways.

Green Stormwater Infrastructure (GSI) practices mimic nature's approach to stormwater management by capturing the rain where it falls, filtering/cleaning the water using soil and plants, and reducing the amount of stormwater by absorbing it into the ground or reusing the captured water. GSI uses natural elements such as soil and plants to turn rainfall into a resource instead of a waste. Practices include absorbent gardens, rainwater reuse, vegetated rooftops, porous pavements, and many more. GSI also provides other environmental and community benefits, such as cooler cities and greener neighborhoods.

Individual property owners may be eligible for Seattle Public Utilities (SPU) RainWise program.
Visit https://700milliongallons.org/rainwise/ to see if your property is eligible.

RainWise is a Seattle rebate program that helps private property owners install cisterns and rain gardens. This helps reduce combined sewer overflows (CSOs), helps prevent flooding, adds attractive landscaping, and can provide water for summer irrigation. RainWise projects capture rainwater that falls on building roof areas up to 5,000 square feet. RainCity projects capture rainwater that falls on impervious areas over 5,000sf total on non-single family parcels. Rebates for RainWise are available in eligible Seattle neighborhoods for work performed by an approved RainWise contractor. Learn more at https://700milliongallons.org/rainwise/