Marin County, CA Right to Farm: Farm Nuisance Protection (2026)

040 states the core right-to-farm rule: an agricultural activity, operation, or facility on agricultural land, run for commercial purposes and consistent with proper and accepted customs and standards, cannot become a legal nuisance under the county code if it was not already a nuisance when it began. 020 as land the Marin Countywide Plan designates Agriculture 1, 2, or 3, or Agriculture and Conservation 1, 2, or 3, or land zoned A, APZ, or ARP; "agricultural operation" covers commercial food and fiber production including cultivation, dairying, viticulture, horticulture, apiculture, and raising of livestock, fish, shellfish, or poultry.

030 sets the policy rationale: because nonagricultural uses increasingly sit next to or inside agricultural areas, farms face nuisance complaints that can force them to curtail operations or discourage investment in farm improvements, so the county chose to protect established operations instead. 050 backs that protection with a mandatory disclosure statement warning that neighboring property may bring "inconvenience or discomfort arising from Agricultural Operations, including but not limited to, noise, odors, fumes, dust, the operation of machinery, the storage and disposal of manure, and the application of chemical fertilizers, soil amendments, herbicides and pesticides," and that such impacts are deemed not to constitute a nuisance if conducted to proper standards.

The county must mail this disclosure to owners of real property in the unincorporated area that is designated agricultural land or adjacent to it; a seller transferring real property on or adjacent to agricultural land, by sale, exchange, installment contract, or lease-to-own, must obtain the buyer's signed acknowledgment of the disclosure; and any discretionary development permit for property on or near agricultural land, including subdivision and land use permits, must include a condition requiring the owner to sign and record the acknowledgment with the county recorder's office.