Costa Mesa, CA Environmental Rules: Coastal Development (2026)

Parts of Costa Mesa, particularly areas near the coast and along the Santa Ana River, fall within the California Coastal Zone as defined by the California Coastal Act of 1976. Since the City of Costa Mesa does not have a certified Local Coastal Program (LCP), the California Coastal Commission retains direct permit authority over development in these areas. Nearly all development within the coastal zone requires a Coastal Development Permit (CDP) from the Commission before work can begin. The Coastal Act defines development broadly to include construction, demolition, grading, changes in land use intensity, and even some changes that do not involve physical construction. Properties within the coastal zone may face additional requirements for solar panel installations, accessory structures, and remodels. The South Coast District Office of the Coastal Commission handles applications for Orange County properties. Standard CDP processing can take 3 to 6 months or longer. Some minor improvements may qualify for a CDP exemption or waiver, but property owners should verify their status with the Commission before starting any work.