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

No rainwater-harvesting prohibition or dedicated permit chapter was found in the Imperial County Title 9 Land Use Ordinance. Rooftop rainwater capture for non-potable outdoor use is generally lawful in California under the Rainwater Capture Act, which lets property owners install and use rooftop rainwater-capture systems for landscape and other approved uses without a water-right permit. At the county level, a rain barrel or cistern is treated like any other site improvement: it must comply with general Title 9 site, drainage, and building standards, and a larger storage tank or any plumbing tie-in can trigger the county's building/plumbing code review under Title 9 Division 10. Imperial County receives only a few inches of rain per year, so harvested rainwater is a minor supplement; the county's water-conserving landscape rules (Title 9 Division 3) instead emphasize drip irrigation, rain-shutoff controllers, mulch, and capping supplemental water at an average of 30 inches/year. Because the prompt's primary sources do not show a county rainwater ordinance, the honest answer is that there is no specific county rule beyond ordinary building and drainage requirements, and state law is permissive.