Fontana, CA Environmental Rules: Flood Elevation Requirements (2026)
Key Facts
- Residential floor elevation
- At or above base flood level
- AO zone floor height
- Depth number on FIRM, 2 ft minimum
- Freeboard added
- None beyond FEMA base flood level
- Certification
- Registered engineer or surveyor elevation certificate
- Enclosed lower areas
- 1 sq in vent per sq ft, flood vents
Summary
New and substantially improved homes in Fontana's mapped flood zones must have the lowest floor, including any basement, built at or above the base flood elevation shown on the FEMA flood insurance rate map. Fontana requires elevation to the base flood level itself; the code does not add extra freeboard above that federal minimum.
Sec. 12-39. - Standards of construction. In all areas of special flood hazards, the following standards are required: ... (3)Elevation and floodproofing. ... c.2.Require that all new construction and substantial improvements of residential structures within zones A1-30, AE and AH zones on the community's FIRM have the lowest floor, including basement, elevated to or above the base flood level. ... c.7.Require that within an AO zone on the community's FIRM that all new construction and substantial improvements of residential structures have the lowest floor, including basement, elevated above the highest adjacent grade at least as high as the depth number specified in feet on the community's FIRM, at least two feet if no depth number is specified.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 64 | Zoning and Development Code: Supplement 17).
Full Breakdown
Sec. ' Nonresidential structures get an alternative under Sec. 3: they may either meet the same elevation, or be built watertight below the base flood level with walls impermeable to water and structural components able to resist hydrostatic and hydrodynamic loads, certified by a registered engineer or architect. In shallow-flooding AO zones, Sec. ' Sec. 12-38(4) requires the property owner or applicant to furnish the floodplain administrator with a registered engineer's or surveyor's certification of the elevation actually achieved, in relation to mean sea level, for every new or substantially improved structure in a special flood hazard area, plus floodproofing certifications for nonresidential buildings that go the watertight route.
Fully enclosed areas below the lowest floor used only for parking, access or storage must have flood vents under Sec. 5: at least two openings totaling one square inch of net area per square foot of enclosed space, with opening bottoms no higher than one foot above grade.
Violations & Fines
Building or substantially improving a residential structure in a mapped zone without elevating the lowest floor to or above the base flood level violates Sec. 12-39(3)c.2 and is enforced through the Sec. 12-32 misdemeanor penalty and the floodplain administrator's permit review. Failing to submit the required elevation certification under Sec. 12-38(4) blocks final approval of the flood zone permit.
Frequently Asked Questions
How high above the base flood elevation must a new Fontana home be built?
Can a garage sit below the base flood elevation?
Who certifies that a structure meets the elevation requirement?
Sources & Official References
Other rules in Fontana
California rules heatmap·Compare Fontana to another location·View the California environmental rules overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
Flood Elevation Requirements in Nearby Cities
How other cities in San Bernardino County handle flood elevation requirements.