Newport Beach, CA Environmental Rules: Stormwater Management (2026)

Newport Beach operates under the Santa Ana Regional Water Quality Control Board's Municipal Separate Storm Sewer System (MS4) NPDES permit. The city's Water Quality program within the Public Works Department enforces stormwater regulations affecting all properties. Construction projects disturbing 500 square feet or more must file a Water Quality Management Plan (WQMP) and implement construction-phase best management practices including silt fences, fiber rolls, stabilized construction entrances, and proper material storage. Projects disturbing one acre or more require a state Construction General Permit with a Stormwater Pollution Prevention Plan (SWPPP). Post-construction requirements apply to new development and redevelopment projects creating or replacing 2,500 square feet or more of impervious surface. These projects must include permanent water quality treatment features such as bioretention planters, permeable pavement, infiltration basins, or proprietary treatment devices. NBMC Chapter 14.36 prohibits non-stormwater discharges to the storm drain system including wash water, pool drainage, irrigation runoff, and other polluted flows. Annual dry weather and wet weather monitoring ensures compliance throughout the city.