Roseville, MN Environmental Rules: Flood Elevation Requirements (2026)

Section 1015.02(c) of the Roseville City Code defines the regulatory flood protection elevation as an elevation no lower than one foot above the elevation of the regional flood plus any increases in flood elevation caused by encroachments on the floodplain that result from designation of a floodway. That one foot is the freeboard. The definitions in subsection (h) tie the regional flood to a 100-year recurrence interval and make it synonymous with the base flood, the one percent annual chance flood, and the 100-year flood elevation.

The lowest floor definition decides what must clear the elevation. It is the lowest floor of the lowest enclosed area, including a basement, but an unfinished or flood-resistant enclosure used solely for parking of vehicles, building access, or storage in an area other than a basement is not counted.

Section 1015.05(b) applies the elevation in the flood fringe district. All structures, including accessory structures, must be elevated on fill so the lowest floor, including basement floor, is at or above the regulatory flood protection elevation. The finished fill elevation can be no lower than one foot below that elevation, and the fill must extend at that elevation at least 15 feet beyond the outside limits of the structure. Accessory structures that do not exceed 500 square feet at their largest projection can instead be floodproofed, and storage of materials or equipment must be elevated on fill to the regulatory flood protection elevation. Residential basement construction is not allowed below it. Nonresidential basements below it are allowed only if structurally dry floodproofed to the FP-1 or FP-2 classification in the state building code.

Where the flood maps show Zone A without a determined elevation, Section 1015.06 makes the applicant furnish the information needed to establish the one percent annual chance flood elevation under approved FEMA methods, following Minn. Rules 6120.5000 to 6120.6200 and 44 CFR 65. Section 1015.03(b)(2) requires as-built elevations for elevated or floodproofed structures to be certified by ground surveys.