Cass County, MO Environmental Rules: Flood Elevation Requirements (2026)
Key Facts
- Freeboard standard
- 2 ft above Base Flood Elevation
- Applies to
- New/substantially improved homes in FW, FF, A Zone
- Foundation
- Permanent, permanently anchored
- Verification
- Elevation Certificate by licensed surveyor/engineer
- Governing sections
- §§ 400.430, 400.460
- Penalty
- $100/day fine, misdemeanor, § 400.490
Summary
Cass County's Floodplain Management Order requires new or substantially improved residences in flood-hazard districts to have their lowest floor elevated at least two feet above the Base Flood Elevation, the county's freeboard standard defined at Zoning Order § 400.430 and applied at § 400.460(B).
FREEBOARD A factor of safety to limit damage above a Base Flood Elevation (BFE). ... Freeboard for this Order is two (2) feet above the Base Flood Elevation. ... All residences to be placed or substantially improved to more than fifty percent (50%) of the current market value within the FW, FF and the A Zone districts shall be elevated on a permanent foundation such that the lowest floor of the home is at least two (2) feet above Base Flood Elevation (BFE) and shall be permanently anchored to said foundation. Where no Base Flood Elevation is known, the applicant shall provide analysis and field measurement adequate to establish a BFE. Such analysis and measurement shall be provided by a registered engineer. An Elevation Certificate for the lowest floor of the structure, provided by a licensed land surveyor or civil engineer will be required upon completion of the building.
Full Breakdown
430 as 'a factor of safety to limit damage above a Base Flood Elevation (BFE),' compensating for unknown factors such as wave action, clogged bridge openings, and topography changes in the watershed that could push flood heights above the calculated BFE; Cass County sets that freeboard at two feet above the Base Flood Elevation. 460(B) turns that definition into a building requirement: any residence to be placed or substantially improved to more than fifty percent of its current market value within the FW, FF, or unnumbered A Zone districts must be elevated on a permanent foundation so the lowest floor sits at least two feet above the BFE, and the foundation must be permanently anchored.
Where no BFE has been established for a site, a registered engineer must provide the analysis and field measurement needed to set one, and once construction is finished, a licensed land surveyor or civil engineer must supply an Elevation Certificate for the lowest floor. 480(2), either by elevating the lowest floor two feet above BFE or by flood-proofing the structure below that level so it is watertight, with a registered professional engineer certifying the FEMA flood-proofing standard has been met. 460(D)(2).
Violations & Fines
Section 400.490 makes failing to elevate a structure to the required freeboard a misdemeanor, punishable by a fine of not more than $100.00 plus the county's costs and expenses, with each day the violation continues beyond the first counted as a separate offense. Because an Elevation Certificate is required at completion under § 400.460(B), the county can also decline to finalize a building permit or certificate of occupancy until the two-foot freeboard above Base Flood Elevation is documented and verified.
Frequently Asked Questions
How high above the flood elevation must a Cass County home be built?
What is 'freeboard' in the Cass County flood code?
Do I need proof that my house meets the Cass County freeboard requirement?
Sources & Official References
Other rules in Cass County
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