Showing ordinances that apply to Lake Holm, WA
Lake Holm is an unincorporated community (population 3,430) in King County, Washington. Because Lake Holm is not an incorporated city, it does not have its own municipal code. Instead, King County ordinances apply directly to properties here. The rainwater harvesting rules below are the ones that govern your area.
Rainwater harvesting is legal and encouraged in Washington under Department of Ecology policy. In unincorporated King County, rooftop capture for on-site use needs no water right and is promoted for stormwater control.
Washington Department of Ecology issued a 2009 interpretive policy confirming that rooftop rainwater harvesting for on-site beneficial use does not require a water right permit and is not restricted under state law. This makes Washington one of the most rainwater-friendly states. King County actively promotes rainwater capture as a stormwater best management practice because Puget Sound receives high annual rainfall and salmon-stream peak flows benefit from slowed runoff. Residents can install rain barrels, cisterns, and underground storage tanks to capture rooftop runoff for landscape irrigation, toilet flushing, or (with appropriate treatment) indoor potable uses under the Washington Plumbing Code and DOH rules. Rain gardens and bioretention are encouraged under the 2019 Stormwater Design Manual for single-family lots. Large cisterns over 5,000 gallons or systems supplying potable indoor fixtures may require plumbing and building permits through the Permitting Division. The RainWise Program (a partnership between King County, Seattle Public Utilities, and participating cities) offers rebates for rain gardens and cisterns in targeted CSO-overflow basins.
Noncompliant plumbing cross-connection: health department notice. Structural cistern without permit: stop-work and retrofit. Indoor potable use without DOH approval: cease use order.
See how Lake Holm's rainwater harvesting rules stack up against other locations.
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