Westminster, CA Environmental Rules: Flood Elevation Requirements (2026)
Key Facts
- Elevation standard
- Lowest floor to or above BFE
- No added freeboard
- Code requires BFE, not BFE-plus-margin
- BFE definition
- 1%-annual-chance ('100-year') flood elevation, § 8.55.050
- Certification required
- Registered engineer or surveyor verifies as-built elevation
- Governing section
- § 8.55.160(C)(1)
Summary
Westminster requires new or substantially improved residential structures in a mapped special flood hazard area to elevate the lowest floor, including any basement, to or above the base flood elevation shown on the FEMA Flood Insurance Rate Map, per § 8.55.160(C)(1). The city does not add a freeboard cushion above that federal BFE: the standard is elevation 'to or above' BFE, not BFE-plus-a-foot.
Residential Construction. All new construction or substantial improvements of residential structures shall have the lowest floor, including basement: a. In an AO zone, elevated to or above the base flood elevation. b. In an AO zone, elevated above the highest adjacent grade to a height equal to or exceeding the depth number specified in feet on the FIRM, or elevated at least two feet above the highest adjacent grade if no depth number is specified. c. In an A zone, without BFEs specified on the FIRM [unnumbered A zone], elevated to or above the base flood elevation; as determined under Section 8.55.140(C).
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4982734; v10 updated 2026-06-10).
Full Breakdown
140(C). Where the FIRM shows only a flood depth number rather than a BFE, the lowest floor must be raised above the highest adjacent grade by that depth number, or by at least two feet if no depth number is given. 160(C)(1)). 160(C)(2)). 160(C)(5)).
Violations & Fines
Building or substantially improving a residential structure without meeting the § 8.55.160(C)(1) elevation standard is enforced the same way as any other Chapter 8.55 violation: constructing without full compliance is a misdemeanor under § 8.55.080, and the floodplain administrator can deny or hold up the development permit required by § 8.55.130 until the elevation certification is corrected.
Frequently Asked Questions
Does Westminster require extra freeboard above the base flood elevation?
What is the base flood elevation Westminster uses?
Who verifies that a new home was built high enough?
Can a detached garage sit below the base flood elevation?
Sources & Official References
Other rules in Westminster
California rules heatmap·Compare Westminster to another location·View the California environmental rules overview
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Flood Elevation Requirements in Nearby Cities
How other cities in Orange County handle flood elevation requirements.