Gallatin County Bridge Report Card
Gallatin County scores 77 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Gallatin County, Montana
Gallatin County has 212 bridges in the National Bridge Inventory, with 12 rated poor and 11 rated scour-critical. Its poor-condition share of 5.7% is at or below the 7.4% statewide average. Poor-condition bridges carry about 16,291 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Gallatin County a Bridge Condition Exposure Score of 77/100 (C). The county has 212 bridges in the National Bridge Inventory, including 12 in poor condition and 11 rated scour-critical. Poor-condition bridges carry about 16,291 daily vehicle crossings. Poor condition does not mean unsafe; bridges judged unsafe are closed or restricted by transportation agencies.
How the Score Breaks Down
| Factor | Weight | County Value | Penalty |
|---|---|---|---|
| Poor-condition bridge share | 40 | 5.7% | 11.3 |
| Poor-condition traffic exposure | 25 | 1.9% of measured traffic | 1.4 |
| Scour-critical bridge share | 20 | 5.2% | 10.4 |
| Average age vs national baseline | 10 | 48 years vs 48 nationally | 0.1 |
| Traffic-data completeness | 5 | 869,885 measured daily crossings | 0.0 |
Score = 100 minus weighted penalties. The score is a comparative research signal, not an official safety rating. Read the full methodology.
County Comparisons
| County Poor-Condition Share | 5.7% |
| State Poor-Condition Share | 7.4% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 5.2% |
| Average Bridge Age | 48 years |
| Poor-Condition Traffic Exposure | 16,291 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Gallatin County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Old Town RD over Jefferson River 063 | Poor condition + traffic exposure | Poor | 100 | 1894 |
| I 90 over Abandoned Rr | Poor condition + traffic exposure | Poor | 8,575 | 1969 |
| US 191 Fh 42 over Teepee Creek | Poor condition + traffic exposure | Poor | 2,605 | 1962 |
| US 191 over Grayling Creek | Poor condition + traffic exposure | Poor | 2,605 | 1962 |
| W Dry Creek RD over Baker Creek | Poor condition + traffic exposure | Poor | 1,287 | 1967 |
| Axtell Anceny RD over Gallatin River 084 | Poor condition + traffic exposure | Poor | 569 | 1919 |
| Old Town RD over Jefferson River 004 | Poor condition + traffic exposure | Poor | 100 | 1897 |
| Maiden Rock RD over Bridger Creek 107 | Poor condition + traffic exposure | Poor | 100 | 1922 |
| Maiden Rock RD over Bridger Creek 106 | Poor condition + traffic exposure | Poor | 100 | 1940 |
| Stagecoach Trl RD over Baker Creek 082 | Poor condition + traffic exposure | Poor | 100 | 1959 |
Important safety note
Poor condition does not mean a bridge is unsafe. It means at least one major component has significant deterioration and the bridge is a priority for maintenance, repair, or replacement. Bridges judged unsafe are closed or restricted by transportation agencies.