On-going maintenance is essential to keep your RainWise installation working properly.

Seattle Public Utilities and King County are counting on your RainWise project to prevent polluted stormwater from going into our waterways. Your cistern and/or rain garden is made possible with public funds. In return, RainWise requires homeowners to maintain their RainWise project for five years.

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Understand Your RainWise Commitment


RainWise customers and cistern

Cistern Maintenance

Remember every September to open the cistern valve (usually red-handled) so that water flows into your rain garden or side sewer. This ensures your cistern empties after each storm and is ready to fill with more water during the next rainfall.

Avoid a clogged cistern by clearing your gutters of leaves and debris before rain and wind push them down to your cistern screen.

Learn about the twice a year easy steps to care for your cistern.


Rain Garden Maintenance

Plants need your help to survive, especially the first few years.

Learn how to identify weeds, how to mulch and when to water.