Mission Viejo, CA Environmental Rules: Stormwater Management (2026)

65, the Water Quality Code, implements the city's Clean Water Act obligations as a co-permittee under the NPDES municipal stormwater permit issued by the San Diego Regional Water Quality Control Board. 200 makes it unlawful for any person to construct, maintain, operate or utilize an illicit connection to the stormwater drainage system, or to cause, allow or facilitate a prohibited discharge, including through an agent, employee or contractor. The prohibition reaches connections established before the chapter's 2010 adoption: legal nonconforming connections tied to structural improvements lose their protection five years after adoption, while nonstructural connections lose it six months after the owner receives written notice identifying the nonconforming connection.

Liability attaches regardless of the violator's negligence or intent. If an authorized inspector determines a discharge that would otherwise fall within the chapter's discharge exception (stormwater, EPA/NPDES-authorized flows, dechlorinated pool water, individual car washing, and similar listed categories) is nonetheless adversely affecting receiving waters, the inspector can give 30 days' written notice ending the exception for that discharge. Property owners with a legal nonconforming connection may request an administrative hearing under Sec. 505(f)-(j) and ask the director for an extension of use, weighed against the risk to receiving waters and the discharger's economic investment.

Enforcement under Division 5 layers notices of noncompliance (compliance deadlines up to 90 days, extendable another 90 for good cause), administrative compliance orders, cease-and-desist orders, and invoices for the city's actual enforcement costs, which become collectible debts if unpaid or unsuccessfully appealed. Any person cited who fails to appear risks an arrest warrant.