Letters of Map Revision
| FEMA Case Number | Type | Effective Date | Affected Map Panel(s) | Watercourse |
| 02-08-151A | LOMR-FW | September 3, 2011 | 30031C0816D | Bozeman Creek |
| 11-08-1121A | LOMR-FW | October 8, 2011 | 30031C0819D | Bozeman Creek |
| 12-08-0136A | LOMR-FW | March 22, 2012 | 30031C0567D | Baker Creek, Baker Creek West Overflow |
| 12-08-0247A | LOMR-FW | February 09, 2012 | 30031C0569D | Baker Creek West Overflow |
| 12-08-0251A | LOMR-FW | January 17, 2012 | 30031C0806D | East Gallatin River Overflow Reach |
| 12-08-0406A | LOMR-FW | April 5, 2012 | 30031C0806D | East Gallatin River Overflow Reach |
| 12-08-0498A | LOMR-FW | May 22, 2012 | 30031C0790D | West Gallatin River |
| 12-08-0519A | LOMR-FW | May 24, 2012 | 30031C0809D | Bridger Creek |
| 13-08-0031A | LOMR-FW | December 13, 2012 | 30031C0790D | West Gallatin River |
| 13-08-0410A | LOMR-FW | March 2, 2013 | 30031C0819D | Bozeman Creek |
| 13-08-0881A | LOMR-FW | July 16, 2013 | 30031C0836D | East Gallatin River |
| 13-08-1337A | LOMR-FW | October 10, 2013 | 30031C0806D | East Gallatin River Overflow Reach |
| 14-08-0017A | LOMR-FW | November 5, 2013 | 30031C0806D | East Gallatin River Overflow Reach |
| 17-08-0879A | LOMR-FW | June 23, 2017 | 30031C0836D | East Gallatin River |
| 18-08-0629A | LOMR-F | April 11, 2018 | 30031C0615D | East Gallatin River |
| 18-08-0663A | LOMR-FW | May 31, 2018 | 30031C0569D | Baker Creek West Overflow |
| 19-08-0406A | LOMR-FW | March 14, 2019 | 30031C0806D | East Gallatin River Overflow Reach |
| 19-08-0434A | LOMR-FW | April 11, 2019 | 30031C0905D | West Gallatin River |
| 20-08-0102A | LOMR-FW | December 11, 2019 | 30031C0818D | Mathew-Bird Creek |
| 20-08-0500P | LOMR | July 12, 2021 | 30031C0802D 30031C0806D 30031C0808D | East Gallatin River |
| 20-08-0733P | LOMR | October 6, 2021 | 30031C0802D | East Gallatin River |
| 21-08-0464P | LOMR | April 11, 2022 | 30031C00595D | Hyalite West Overflow |
| 21-08-1190P | LOMR | May 6, 2022 | 30031C0790E | West Gallatin River, Shed's Split |
| 22-08-0206A | LOMR-FW | February 9, 2022 | 30031C0790E | West Gallatin River |
| 22-08-0582A | LOMR-FW | June 23, 2022 | 30031C0588E | West Gallatin River |
| 22-08-0585A | LOMR-FW | May 27, 2022 | 30031C0905E | West Gallatin River |
| 22-08-0804A | LOMR-FW | May 27, 2022 | 30031C0905E | West Gallatin River |
| 22-08-0739A | LOMR-FW | December 7, 2022 | 30031C0802D | Buster Gulch |
| 23-08-0301P | LOMR | September 18, 2023 **not yet adopted by Gallatin County** | Flood Profiles: 203P, 204P, 207P, 209P, 210 P 212P-219P, and 222P- 230P Floodway Date Table 8 | West Gallatin River Profile Correction |