Merced, CA Swimming Pools & Spas: Hot Tub Rules (2026)

Hot tubs and spas in the City of Merced are addressed through the same provisions as swimming pools. The state Swimming Pool Safety Act, adopted locally by MMC Section 17.05.010 through Appendix CI of the 2025 California Residential Code, defines a "swimming pool or spa" together and applies its drowning-prevention requirements to spas as well as pools. MMC Section 20.28.020.D therefore applies to spas: a 5-foot setback from all property lines (unless the building code allows otherwise) and barriers "as required by the building code and state law." Under HSC Section 115922, a new or remodeled spa at a single-family home must have at least two of the seven approved safety features. For many residential spas, an approved safety pool/spa cover meeting the ASTM F1346 standard is a commonly used feature and, combined with a second qualifying feature, satisfies the requirement. A building permit is typically required for permanent spa installations and for the associated electrical work, administered by the Merced Building Division. Note that the City's noise standards in the Municipal Code may also apply to spa equipment such as pumps and blowers; MMC Section 20.48.040 (for home occupations) and general nuisance provisions reflect Merced's broader policy against impacts perceptible beyond a property line, which is a useful guide for keeping spa equipment from disturbing neighbors.