Bridge conditions in Sheridan County, Montana
66 inventoried bridges · 3 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 66 bridges in Sheridan County: 11 rated good, 52 fair, and 3 poor.
- 3 of the 66 bridges in Sheridan County, Montana, are rated in poor condition (4.5%) in the 2025 National Bridge Inventory, as of .
- 11 bridges (16.7%) are rated good and 52 (78.8%) fair.
- The median Sheridan County bridge was built in 1983.
- The busiest poor-rated bridge is S 5 over Dahl Creek (built 1939), carrying about 309 vehicles a day.
Good 16.7% · Fair 78.8% · Poor 4.5% of 66 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| S 5 over Dahl Creek | 1939 | 309 | Poor |
| S 5 over Main Creek | 1939 | 309 | Poor |
| W Lake Rd over Big Muddy Creek 046 | 1950 | 79 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| S 5 over Marron Creek | 1983 | 1,559 | Fair |
| S 16 over Ator Creek | 1984 | 1,559 | Fair |
| S 5 over Antelope Creek | 1986 | 1,120 | Good |
| S 16 over Medicine Lake | 1975 | 891 | Fair |
| S 5 over Plentywood Creek | 2001 | 589 | Good |
| S 5 over Mccoy Creek | 2001 | 589 | Good |
| S 5 over Redstone Creek | 2011 | 511 | Good |
| S 5 over Big Muddy Creek | 2012 | 511 | Fair |
| S 5 over Eagle Creek | 2011 | 323 | Fair |
| S 5 over Dahl Creek | 1939 | 309 | Poor |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Montana: Montana bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.