Hercules, CA Fence Regulations: Retaining Walls (2026)
Key Facts
- Governing sections
- Sec. 7-2.501, 7-2.302, 7-2.509, 7-2.510
- Permit-exempt depth
- Under 5 feet with UBC-designed support
- Max unpermitted slope
- 2:1 slope, 7 feet high
- Enforcing officer
- Hercules City Engineer
- Hazard abatement
- Owner must repair or eliminate on notice
Summary
Hercules requires excavations deeper than 5 feet, or cut slopes steeper than 2:1, to be permitted and supported by an engineered retaining structure. Under Municipal Code Sec. 7-2.501, the City Engineer can require retaining walls or cribbing wherever needed to keep an excavation or fill from exceeding the maximum allowable slope.
Adequate provisions shall be made to prevent any surface waters from damaging the cut face of an excavation or sloping surface of a fill. Retaining walls or cribbing constructed in accordance with the requirements of the City Engineer shall be used wherever necessary to prevent the surface of any excavation or fill from exceeding at any point the maximum allowable slopes set forth herein.
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through Ordinance 555, passed March 25, 2025).
Full Breakdown
Sec. 302(a) of the Hercules grading ordinance exempts only shallow work from the City's grading permit: an excavation under five feet deep that is adequately supported by a retaining structure designed in accordance with the Uniform Building Code, a cut slope no steeper than two horizontal to one vertical and no taller than seven feet, or work under 200 cubic yards. Anything larger or steeper needs a grading permit, and Sec. 501(a) requires that retaining walls or cribbing built to the City Engineer's requirements be used wherever necessary to keep an excavation or fill from exceeding the maximum allowable slopes.
The City Engineer can also order retaining walls or cribbing mid-project as a safety precaution under Sec. 509 if inspection shows the ground formation is likely to endanger property or a public way, and can specify flatter slopes, additional drainage, terracing, or compaction instead. Sec. 504 separately requires anyone excavating near a property line to support and protect any adjoining public street, sidewalk, alley, or private property from settling, cracking, or other damage in a manner the City Engineer approves, and Sec. 510 lets the Engineer order an owner to repair or eliminate an existing excavation, fill, or retaining structure that has become a hazard.
Violations & Fines
Building a retaining wall or leaving a cut slope without the required engineering support, or without the grading permit Sec. 7-2.301 requires once the Sec. 7-2.302 exemption thresholds are exceeded, can bring a stop-work order and permit suspension under Sec. 7-2.320. If the City Engineer finds an existing retaining structure or excavation has become hazardous, Sec. 7-2.510 lets the Engineer order the owner to repair or eliminate it within a stated deadline, at the owner's expense.
Frequently Asked Questions
When does a Hercules retaining wall need a grading permit?
Who decides how a retaining wall must be engineered?
What if a retaining wall on my property becomes a hazard?
Sources & Official References
Other rules in Hercules
California rules heatmap·Compare Hercules to another location·View the California fence regulations overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
Retaining Walls in Nearby Cities
How other cities in Contra Costa County handle retaining walls.