Building in a flood zone in Norco: the local rules

Each rule below links to the section of the Norco Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Norco's code says

Norco code What Norco's code adds
Floodplain permit	A development permit is needed before any construction or development, including manufactured homes, in a special flood hazard area. Applies: Special flood hazard areas. § 15.60.140 · code text A development permit shall be obtained before any construction or other development, including manufactured homes, within any special flood hazard area established in accordance with its definition in Section 15.60.060.
Building in a floodway	No fill, new construction or other encroachment unless analyses certified by a registered civil engineer show no flood level increase. Applies: Within an adopted regulatory floodway. § 15.60.210 · code text Within an adopted regulatory floodway, the City of Norco shall prohibit encroachments, including fill, new construction, substantial improvements, and other development, unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice and certification by a registered civil engineer is provided that the proposed encroachment shall not result in any increase in flood levels within the community during the occurrence of the base flood discharge.
Height of the lowest floor	At least 1 foot above the base flood elevation. Applies: New or substantially improved structures in special flood hazard areas. § 15.60.160 · code text New construction and substantial improvement of any structure shall have the lowest floor, including basement, elevated to at least one foot above the base flood elevation. At least 1 foot higher than the FIRM depth number, above the highest adjacent grade. Applies: New or substantially improved structures in Zone AO with a depth number on the FIRM. § 15.60.160 · code text New construction and substantial improvement of any structure in Zone AO shall have the lowest floor, including basement, elevated above the highest adjacent grade at least one foot higher than the depth number specified in feet on the FIRM, or at least two feet if no depth number is specified. At least 2 feet above the highest adjacent grade. Applies: New or substantially improved structures in Zone AO with no depth number on the FIRM. § 15.60.160 · code text New construction and substantial improvement of any structure in Zone AO shall have the lowest floor, including basement, elevated above the highest adjacent grade at least one foot higher than the depth number specified in feet on the FIRM, or at least two feet if no depth number is specified.

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Frequently asked questions

What are the rules for building in a Norco flood zone?

Norco's code: A development permit is needed before any construction or development, including manufactured homes, in a special flood hazard area. (Special flood hazard areas.) (§ 15.60.140); At least 1 foot above the base flood elevation. (New or substantially improved structures in special flood hazard areas.) (§ 15.60.160).

Building in a flood zone in Norco

What Norco's code says

Who this affects

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