Union City, CA Environmental Rules: Flood Zones (2026)
FEMA flood zone rules in Union City, CA, also called floodplain regulations or special flood hazard area (SFHA) rules, determine flood insurance requirements and elevation standards for new construction.
Key Facts
- Permitting authority
- Economic and Community Development Director
- Flood map source
- FIRM effective February 9, 2000
- Permit needed for
- Construction, filling, grading, dredging
- Violation penalty
- Misdemeanor under § 18.98.030(C)
Summary
Union City requires a development permit before any construction, filling, or grading in a mapped special flood hazard area, and violations of the floodplain chapter are a misdemeanor under the municipal code.
A development permit shall be obtained before construction or development begins within any area of special flood hazards established in Section 18.98.030(B). Application for a development permit shall be made on forms furnished by the Director and may include, but not be limited to: plans in duplicate drawn to scale showing the nature, location, dimensions and elevation of the area in question; existing or proposed structures, fill, storage of materials, drainage facilities.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4940544; v16 updated 2026-06-23).
Full Breakdown
Any area of special flood hazard within Union City limits, mapped on the FEMA Flood Insurance Rate Map effective February 9, 2000, requires a development permit from the Economic and Community Development Director before construction, filling, grading, dredging, or other development begins, per Union City Municipal Code § 18.98.040(A). The permit review confirms the site is reasonably safe from flooding and will not raise the base flood's water surface elevation by more than one foot. Building or altering land in a flood hazard area without complying with Chapter 18.98 is a misdemeanor under § 18.98.030(C).
Violations & Fines
Constructing, filling, grading, or altering land in a mapped special flood hazard area without a development permit is a misdemeanor under Union City Municipal Code § 18.98.030(C); the City Council may take further legal action to remedy the violation.
Frequently Asked Questions
Do I need a permit to build in a Union City flood zone?
What happens if I develop in a flood zone without a permit?
Sources & Official References
Other rules in Union City
California rules heatmap·Compare Union City to another location·View the California environmental rules overview
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Flood Zones in Nearby Cities
How other cities in Alameda County handle flood zones.