Hennepin County, MN Environmental Rules: Flood Zones (2026)

Minnesota floodplain management is governed by Minn. Stat. §§103F.101-103F.165 (Floodplain Management Act). Minn. Stat. §103F.121 requires every city with a mapped floodplain to adopt a floodplain management ordinance, and Minn. Stat. §103F.165 requires NFIP participation when the DNR Commissioner or FEMA determines the city has areas subject to recurrent flooding. The DNR must review and approve all new and amended floodplain ordinances under Minn. Stat. §103F.121, subdivision 3 - an unapproved ordinance is invalid. The state's regulatory framework follows the Minnesota Model Floodplain Ordinance, which regulates three districts: floodway (where flood waters move at high velocity), flood fringe (storage area), and A Zone (general floodplain where detailed studies have not been completed). Hennepin County floodplains are concentrated along the Mississippi River (forming the eastern boundary), the Minnesota River (forming the southern boundary), Minnehaha Creek, Bassett Creek, and several lakes. The state-mandated freeboard requires the lowest floor of new and substantially improved residential structures to be at least 1 foot above the base flood elevation (BFE). Non-residential structures may alternatively be dry-floodproofed to 1 ft above BFE. Substantial improvement applies when reconstruction, repair, or improvement equals or exceeds 50% of pre-improvement market value, triggering full ordinance compliance. Federal NFIP standards are at 44 CFR Parts 59-60. Minneapolis, Bloomington, Edina, Minnetonka, Hopkins, St. Louis Park, and other Hennepin cities are NFIP participants. Floodplain Use Permits are required for any development - including grading, fill, and structures - within a Special Flood Hazard Area before a building permit is issued.