Sweet Grass County Floodplain Administration

Sweet Grass County is a participant in the National Flood Insurance Program (NFIP) and has adopted a 100 year floodplain for the Yellowstone River and portions of other streams in the county, including the Boulder River, East Boulder, Elk Creek, Big Timber Creek, Upper and Lower Deer Creek, Spring Creek, Sweet Grass Creek, and Bridger Creek.  The County Planner is the Floodplain Administrator for Yellowstone County.

The floodplain regulations shall apply to all lands within the jurisdiction of the County of Sweet Grass, State of Montana, shown on maps and other documents as being located within a mapped 100-year floodplain.

The Sweet Grass County and City of Big Timber floodplain maps have been updated in conjunction with a nationwide effort to modernize floodplain maps for floodprone communities.  The new Floodplain Ordinance have been adopted and are effective May 18th, 2015. With the new ordinance the review fee has been increased to $150. Sweet Grass County’s existing floodplain maps were produced in 1982 and have been updated and digitized. Those digital maps are now available at the Planning office or online at:  https://msc.fema.gov/portal/

Development within the designated flood hazard areas must be reviewed to determine exemptions from or compliance with floodplain regulations or need for a floodplain permit. Relevant floodplain documents include:

Sweet Grass County Floodplain Regulations
City of Big Timber Floodplain Regulations 2015
Joint Application Form – 310 floodplain permit This application is the Joint Application for Proposed Work in Montana’s Streams, Wetlands, Floodplains and Other Water Bodies and Instructions

Additional helpful links:
DNRC publishes a guide to a variety of permits that may be required for work in and around Montana streams. That guide can be found at: http://dnrc.mt.gov/Permits/StreamPermitting/Guide.asp