Ontario requires a permit for any retaining wall over 4 feet (footing to top) or carrying a surcharge such as a slope or driveway. Engineered plans by a licensed California civil or structural engineer are required.
Under the California Building Code as adopted by Ontario, a retaining wall is exempt from building permit requirements only when it is 4 feet or less in height measured from the bottom of the footing to the top of the wall AND it does not support a surcharge load. A surcharge includes any slope rising above the wall, driveway, vehicular load, pool deck, structure, or impounded water. Any retaining wall above 4 feet or carrying a surcharge requires a building permit with engineered plans from a licensed California civil or structural engineer showing footings, reinforcement, drainage, and lateral loads. Walls near property lines must also meet zoning setbacks and neighbor notification, and drainage cannot be directed onto neighboring parcels. Walls in hillside areas or near geologic hazards may require additional soils and grading review. Failure to permit a retaining wall creates substantial liability for failures, settlement, and drainage damage to neighbors, and Code Enforcement can require after-the-fact permits or removal.
Contact your local code enforcement office for specific penalty information.
Ontario, CA
Outdoor music is regulated under OMC Title 5 Chapter 29 and the special-event permit process. Venues and events with amplified sound need a city permit; resi...
Ontario, CA
Aircraft noise from Ontario International Airport (ONT) is regulated by the FAA, not the city. ONT runs an FAA Part 150 noise compatibility program; federal ...
Ontario, CA
Ontario requires dogs to be leashed off-property under OMC Title 6. Maximum leash length is 6 feet, with owner control required in all public spaces except d...
Ontario, CA
Ontario allows beekeeping under the Development Code with hive-count and setback limits. Beekeepers must register annually with the San Bernardino County Agr...
Ontario, CA
Ontario allows backyard fire pits under the California Fire Code as adopted. Wood pits must sit 25 feet from structures and be attended. SCAQMD no-burn days ...
Ontario, CA
All fireworks, including Safe and Sane, are banned in Ontario year round under Ontario Municipal Code and California Health and Safety Code 12500. Fines star...
Side-by-side rule comparisons with other cities in San Bernardino County.
See how other cities in San Bernardino County handle retaining walls.
See how Ontario's retaining walls rules stack up against other locations.
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