Newport Beach, CA Fence Regulations: Retaining Walls (2026)

Newport Beach requires a building permit for retaining walls exceeding 4 feet in height measured from the bottom of the footing to the top of the wall. Walls over 4 feet must be designed by a licensed engineer and require structural plan review. When a fence is placed on top of a retaining wall, the combined height is regulated and may trigger additional permit requirements. Grading permits from Public Works may be required when retaining wall construction involves significant earthwork or changes to drainage patterns. Retaining walls in the Coastal Zone may require a Coastal Development Permit, particularly if the wall is visible from public areas or involves changes to the existing grade near the coast. Drainage behind retaining walls must be properly addressed with weep holes, gravel backfill, or subdrain systems to prevent hydrostatic pressure buildup. The city may require geotechnical reports for retaining walls on slopes or in areas with known soil stability issues. Retaining walls along property boundaries must be set back from the property line or require neighbor consent if built on the boundary.