When it rains hard, combined storm and sanitary sewers in some neighborhoods can’t handle all the volume, causing “combined sewer overflows” (CSOs) into the nearest water body.
Homeowners in parts of West Seattle, Ballard and NE Seattle can qualify for rebates that cover the cost of having cisterns or raingardens installed on their property through the City of Seattle’s RainWise Program, which will reduce the amount of water runoff into the sewer system.
Did you get a chance to see the cisterns from EarthSystems NW on the the NW Green Home Tour? They really are amazing. EarthSystemsNW is a contractor for the RainWise program, so if you qualify for the program, you could also be the proud owner of a cistern similar to those on the tour.
In addition to providing a lookup tool to find out if you qualify for these incentives, you can also find a lot of information about rainwater runoff and how small decisions (like the types and placement of the plants you use in your raingarden design) can help with the problem.