Hercules, CA Environmental Rules: Flood Zones (2026)
FEMA flood zone rules in Hercules, CA, also called floodplain regulations or special flood hazard area (SFHA) rules, determine flood insurance requirements and elevation standards for new construction.
Key Facts
- Governing sections
- HMC Sec. 10-7.301, 10-7.302, 10-7.303
- Map basis
- FEMA FIS dated March 30, 1982
- Floodplain Administrator
- Director of Public Works
- Cumulative rise cap
- Max 1 ft increase in base flood elevation
- Violation classification
- Misdemeanor
Summary
Hercules regulates all development within FEMA-designated special flood hazard areas under Chapter 7 of the Municipal Code. The city adopts FEMA's 1982 Flood Insurance Study and maps by reference, and no structure or land may be built, altered, or converted in those areas without full compliance.
Sec. 10-7.301. Lands to Which This Chapter Applies. This Chapter shall apply to all areas of special flood hazards within the jurisdiction of City of Hercules, Contra Costa County.
Sec. 10-7.302. Basis for Establishing the Areas of Special Flood Hazard. The areas of special flood hazard identified by the Federal Emergency Management Agency (FEMA) in the "Flood Insurance Study (FIS) for City of Hercules, Contra Costa County" dated March 30, 1982, with accompanying Flood Insurance Rate Maps (FIRMs) and Flood Boundary and Floodway Maps (FBFMs), dated September 30, 1982, and all subsequent amendments and/or revisions, are hereby adopted by reference and declared to be a part of this Chapter.
Sec. 10-7.303. Compliance. No structure or land shall hereafter be constructed, located, extended, converted, or altered without full compliance with the terms of this Chapter and other applicable regulations. Violation of the requirements (including violations of conditions and safeguards) shall constitute a misdemeanor.
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
301 states that the flood damage prevention chapter applies to all areas of special flood hazard within the jurisdiction of the City of Hercules, Contra Costa County. 302 identifies the basis for that boundary: the areas of special flood hazard identified by FEMA in the Flood Insurance Study for City of Hercules, Contra Costa County dated March 30, 1982, with the accompanying Flood Insurance Rate Maps and Flood Boundary and Floodway Maps dated September 30, 1982, and all subsequent amendments, are adopted by reference and made part of the chapter.
401) can recommend supplemental studies for other areas to the City Council. 303 backs this up with a compliance mandate: no structure or land may be constructed, located, extended, converted, or altered without full compliance with the chapter and other applicable regulations. 304 sets the chapter as a floor, not a ceiling. Where it conflicts with another ordinance, easement, covenant, or deed restriction, whichever imposes the more stringent restriction prevails. 402(a)(4).
Violations & Fines
Section 10-7.303 makes violation of the chapter's requirements, including construction, conversion, or alteration in a special flood hazard area without required compliance, a misdemeanor, and permits the City Council to take further lawful action to prevent or remedy the violation.
Frequently Asked Questions
What areas of Hercules are covered by the floodplain ordinance?
Can I build in a Hercules flood zone without a permit?
Does a new Hercules development have to avoid raising flood levels for neighbors?
Sources & Official References
Other rules in Hercules
California rules heatmap·Compare Hercules 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 Zones in Nearby Cities
How other cities in Contra Costa County handle flood zones.