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

Unincorporated Mono County has no ordinance prohibiting residential rainwater harvesting. California's Rainwater Capture Act of 2012 (AB 1750, Water Code 10574) provides that the use of rainwater collected from rooftops does not require a water-right permit under Water Code 1201, and a simple rain barrel used for outdoor, non-potable purposes (a barrel/cistern under 360 gallons in the statute's rain-barrel provision) can be installed without a state permit when used per manufacturer instructions. Mono County's General Plan reinforces capture: Policy 4.A.8.a directs developers to use low-impact development stormwater solutions including 'rain gardens, green roofs, vegetated infiltration ponds' and similar measures, and Policy 3.C.1 promotes gray-water and conservation systems. Larger cisterns, elevated tanks, or any potable (drinking/cooking) rainwater system are regulated by the California Plumbing Code (including Appendix K for non-potable and potable rainwater catchment) and the California Building Code as adopted by the County, and may require a building permit for structural support, plumbing connections, or treatment. Captured rainwater used for landscape irrigation supports the County's water-conservation objectives.