UPDATE: Madison County will have effective floodplain maps on December 18, 2024.

UPDATE: Broadwater County will have effective floodplain maps on the Jefferson River September 26, 2024. 

 Madison, Jefferson, Gallatin, and Broadwater Counties have been working with the Federal Emergency Management Agency (FEMA) and Montana Department of Natural Resources and Conservation (DNRC) to produce new floodplain maps for portions of the Madison, Ruby, Jefferson, Beaverhead and South Boulder Rivers, and Mill and Indian Creeks.  See project extents here.

Updated floodplain maps will depict the latest, most accurate flood risk data, and will eventually result in updated FEMA floodplain maps. Most of the existing FEMA floodplain maps and Madison County flood prone maps are based on data from the 1980s and 1990s. 

View Draft Maps


 *please be patient while the data loads on the viewer*

Draft or preliminary maps and studies need to go through a lengthy technical and public review process. When finalized, new maps could have effects on some property owners in mapped 100-year floodplains. Click on your county below to learn about the floodplain designations referenced on the maps, community meetings, and other information:

 Past Open House Meetings:
July 19, 2023| Twin Bridges| view slides view video recording
July 20, 2023| Ennis | view slides view video recording 
March 9, 2021 | Madison River | view slides   view video recording

March 10, 2021 | Jefferson River & S. Boulder R. | view slides   view video recording
March 11, 2021 | Ruby & Beaverhead Rivers, Sheridan & Twin Bridges | view slides   view video recording

Flood Insurance Information:

RR-22.0-Rate-Guide.PNG   RR-2.0-Discount-Guide.PNG

For additional questions contact your local floodplain administrator.


Gallatin County

Sean O'Callaghan 
(406) 582-2280

City of Three Forks

Kelly Smith
(406) 285-3431

FEMA issued preliminary maps for Madison County on February 26, 2023.

For more information on what it means to own property in the floodplain please look at the flyers below.

A formal appeal/comment period was held for Madison County, and the Towns of Ennis, Sheridan, and Twin Bridges from August 24, 2023- November 21, 2023.

Madison County

Cody Marxer County Floodplain Administrator

(406) 872-6359

Town of Ennis & Town of Twin Bridges

Jerry Grebenc Towns Floodplain Administrator
(406) 872-6359

Ennis POC
Susie Sprout
(406) 682-4287

Twin Bridges POC
Kristi Millhouse
(406) 684-5243

Town of Sheridan

Mayor Judy Wertz Town Floodplain Administrator
(406) 842-5431


Floodplain Maps will go effective for the County September 26, 2024

Preliminary Floodplain Maps were issued to Broadwater County on October 14, 2022. 

For more information on what it means to own property within in the floodplain please see the flyers below.

A formal appeal period for the Broadwater County preliminary maps was held between May 5, 2023 and end on August 1, 2023. 
For more information on the flood study please contact your local floodplain administrator:
Jerry Grebenc
Broadwater County Floodplain Administrator
(406) 495-6153

Tentative Project Timeline