Cass County, ND Environmental Rules: Flood Zones (2026)

Cass County is an NFIP-participating community and many of its incorporated cities (Fargo, West Fargo, Horace, Casselton, Mapleton, Argusville) participate as well, per the FEMA Community Status Book for North Dakota. The Cass County Flood Damage Prevention Ordinance (administered by the County Engineer's office and the County Planner) governs development inside FEMA-mapped Special Flood Hazard Areas in unincorporated areas. Property owners must obtain a development permit before any construction, substantial improvement, fill, or grading in the floodplain. Cass County's Flood Insurance Rate Maps (FIRMs) are being updated by FEMA, and a formal flood map appeal period has been published on FEMA.gov. Federal NFIP standards live at 44 CFR Parts 59-60 and require, at minimum, that the lowest floor of new residential construction be elevated to or above the base flood elevation. State-level floodplain authority comes from NDCC Chapter 61-16.1, administered by the North Dakota Department of Water Resources. The county also works with the Metro Flood Diversion Authority on the Fargo-Moorhead diversion project that protects the metro area against Red River floods. Property owners should consult both the FEMA Flood Map Service Center (msc.fema.gov) and the Cass County Planning Office before any work in or near the Red River, Sheyenne River, Maple River, or Rush River floodplains.