Louisville, KY Landscaping Rules: Rainwater Harvesting (2026)

Kentucky has no statewide statute restricting collection of rainwater from a private rooftop, and the Louisville Metro Code of Ordinances contains no chapter prohibiting or permitting rain barrels, cisterns, or other rainwater harvesting devices for landscape irrigation. Residential rain barrels do not require a building permit when used outdoors at grade for non-potable uses such as garden watering. Louisville and Jefferson County Metropolitan Sewer District (MSD) actively encourages harvesting: it operates a 58-gallon rain barrel program with the Louisville Nature Center, where food-grade barrels are converted by Louisville Youthbuild and sold at workshop pricing. MSD also pays a one-time $100 incentive for each downspout legally disconnected from the combined sewer system under its Downspout Disconnection Program (call MSD Customer Relations at 502.540.6000 or email CustomerRelations@LouisvilleMSD.org for an inspection before doing work). Larger cisterns, indoor plumbing connections, or systems intended for potable or graywater reuse fall under the Kentucky Plumbing Code (815 KAR 20:191) and require a plumbing permit and backflow prevention. New developments of one acre or more must implement Green Infrastructure / Best Management Practices under MSD's 2013 design regulations, where harvesting structures may count toward stormwater volume credits. Cross-connection to the public water supply is prohibited under MSD wastewater/stormwater discharge regulations.