Nevada County, CA Landscaping Rules: Rainwater Harvesting (2026)

Nevada County imposes no prohibition on capturing rainwater, and the County actively promotes on-site water conservation. The controlling law is the California Rainwater Capture Act of 2012, which allows residents, businesses, and public entities to install and use rooftop rainwater-collection systems (rain barrels and cisterns) without obtaining a State Water Resources Control Board appropriative water-right permit. There is no statewide volume cap on rooftop collection. SB 558 (2018) added a property-tax exclusion for new residential rainwater-capture systems, further encouraging adoption. At the county level, the practical requirements are building- and health-code based rather than prohibitive: simple gravity rain barrels generally need no permit, but larger storage tanks, elevated or structurally significant cisterns, or systems that connect into household plumbing can trigger a Nevada County building permit and must comply with the California Plumbing Code (especially if the captured water is used indoors or pressurized). Mosquito control matters too - tanks should be screened to prevent breeding, consistent with public-health expectations. Captured rainwater is a common way to meet the on-site stormwater-capture and irrigation goals embedded in California's water-efficient landscape rules. Owners planning a sizable system should confirm permit thresholds with the Nevada County Community Development Agency (530-265-1222).