
Butte-Silver Bow County has been working with The Department of Environmental Quality (DEQ) and Pioneer Technical to complete the Silver Bow Creek/Streamside Tailings Superfund remediation project. The cleanup, which consisted of removing six million yards of tailings (mine waste containing heavy metals) and related impacted soils from the floodplain of Silver Bow Creek, the reconstruction of the stream channel and floodplain, and re-vegetation of the affected area, has been completed. As a result of this cleanup, a floodplain mapping revision is required.
When finalized, the new revised maps could have effects on some property owners in the mapped floodplain. If you are currently or will be shown in a 100-Year Floodplain, see the 100-Year Floodplain link to understand what may mean for you.
Finalizing the Maps and Study
FEMA held a 90-day comment and appeal period about the proposed floodplain map changes for Silver Bow Creek May 6 - August 4, 2021.
FEMA is currently in the process of finalizing the Flood Insurance Rate Maps and updating the county's Flood Insurance Study. The updated maps and report are expected to go into effect on June 1, 2022, and will replace the existing Silver Bow Creek floodplain maps and county Flood Insurance Study.
View Preliminary Floodplain Maps
Click on the link below to see the proposed floodplain maps and how the preliminary maps compare to the existing FEMA floodplain maps on an interactive map viewer. 
or you can view individual preliminary maps here:
Preliminary Flood Insurance Rate Maps and Flood Insurance Study
Get more information on floodplain designations referenced on the maps:
View Technical Reports:
Hydrology Report
Hydraulic Report
Project Timeline

For more information, contact:
Dylan Pipinich
Butte- Silver Bow County
dpipinich@bsb.mt.gov
(406) 497-6256
Tiffany Lyden
DNRC
Tlyden@mt.gov
(406) 444-0599
Nadene Wadsworth
DNRC
Nadene.Wadsworth@mt.gov
(406) 444-6732