Merced, CA Landscaping Rules: Rainwater Harvesting (2026)

Harvesting rainwater from your roof for landscape use is legal and uncontroversial in Merced. There is no City of Merced ordinance banning rain barrels or rooftop rainwater collection. State law is favorable: the California Rainwater Capture Act of 2012 (AB 1750) provides that the use of rainwater collected from rooftops does not require a water-right permit from the State Water Resources Control Board, and a landowner is not required to obtain a permit from a local public agency to install, maintain, or operate a rain-barrel system, except where installation requires disconnecting a downspout from the sewer (then a permit may apply for the proper sewer cap). Notice to the water utility is not required for a rain-barrel system using a cistern under 360 gallons. Because Merced draws 100 percent of its supply from local groundwater and participates in SGMA compliance through groundwater pool and integrated regional water management efforts, the City promotes conservation generally. Rain barrels reduce reliance on potable groundwater for irrigation and complement the City's address-based watering schedule. Larger rainwater systems, structures, or plumbing tie-ins may still require standard building or plumbing permits, and any captured water used for irrigation should follow the City's broader water-conservation regulation. Always keep barrels screened and covered to avoid creating a mosquito or vector nuisance.