Olmsted County, MN Environmental Rules: Flood Zones (2026)
FEMA flood zone rules in Olmsted County, MN, also called floodplain regulations or special flood hazard area (SFHA) rules, determine flood insurance requirements and elevation standards for new construction.
Key Facts
- County Ordinance
- Chapter 3750 (Ord. 23-5)
- State Authority
- Minn. Stat. Ch. 103F
- Federal Authority
- 44 CFR Parts 59-60 (NFIP)
- Regulated Waters
- Zumbro River + tributaries
- Zone Map Source
- FEMA FIRM (msc.fema.gov)
- Substantial Improvement
- 50% of market value
- Administering Agency
- Olmsted County Planning Dept.
Summary
Olmsted County participates in the FEMA National Flood Insurance Program and administers floodplain rules through Chapter 3750 - Floodplain and Shoreland Ordinance (Ordinance No. 23-5). The ordinance regulates development along the Zumbro River and its tributaries, requires Department of Natural Resources approval and FEMA notification for changes to base flood water surface elevations, and applies Minnesota's statutory floodplain framework under Minn. Stat. Ch. 103F (Floodplain Management). The Olmsted County Planning Department administers and enforces the ordinance.
Section 4.01 LAND TO WHICH ORDINANCE APPLIES. (A) This ordinance applies to all lands within the jurisdiction of Olmsted County within the boundaries of the Floodway, Flood Fringe and General Floodplain Districts. (B) The Floodway, Flood Fringe or General Floodplain Districts are overlay districts. The standards imposed in the overlay districts are in addition to any other requirements. In case of a conflict, the more restrictive standards will apply. (C) Where a conflict exists between the floodplain limits illustrated on the official floodplain maps and actual field conditions, the Base Flood Elevation (BFE) shall be the governing factor in locating the outer boundaries of the one-percent annual chance floodplain.
Official source re-checked September 7, 2026: the cited page had not changed since it was quoted.
Full Breakdown
Floodplain regulation in Minnesota is anchored in Minn. Stat. Ch. 165, which require local governments with mapped floodplains to adopt and enforce a floodplain ordinance meeting Department of Natural Resources standards. Counties and cities must also satisfy federal NFIP rules at 44 CFR Parts 59-60 to keep their communities eligible for federally backed flood insurance. Olmsted County adopted Chapter 3750 - Floodplain and Shoreland Ordinance (Ordinance No. 23-5) to comply with both frameworks. Chapter 3750 regulates development in the FEMA-mapped Special Flood Hazard Area along the Zumbro River and its tributaries, including the floodway, flood fringe, and general floodplain districts.
Under Chapter 3750, any change to base flood water surface elevations requires notification to FEMA and approval by the Minnesota DNR. The ordinance is administered and enforced by the Olmsted County Planning Department. New residential structures in the SFHA must have the lowest floor elevated above the regulatory flood protection elevation set by the ordinance (Minnesota's statewide minimum is one foot above the base flood elevation per DNR rules at Minn. Rules Ch. 6120). Substantial improvements - those equal to 50% or more of the structure's pre-improvement market value - trigger full floodplain compliance.
The City of Rochester has a separate floodplain overlay within its UDC. FEMA Flood Insurance Rate Maps for Olmsted County can be obtained through the FEMA Map Service Center.
Violations & Fines
Development in the floodplain without the required permit, or below the ordinance's regulatory flood protection elevation, violates Olmsted County Chapter 3750 and Minn. Stat. Ch. 103F. Remedies include stop-work orders, denial of building permits, civil penalties, and orders to remove or elevate noncompliant structures. Persistent violations can jeopardize the community's NFIP participation and disqualify property owners from federally backed flood insurance.
Frequently Asked Questions
Is my Olmsted County property in a flood zone?
What permit do I need to build in the Olmsted County floodplain?
Sources & Official References
Other rules in Olmsted County
Compare Olmsted County to another location·View the Minnesota environmental rules overview
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