Cassia County Bridge Report Card
Cassia County scores 93 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Cassia County, Idaho
Cassia County has 117 bridges in the National Bridge Inventory, with 0 rated poor and 4 rated scour-critical. Its poor-condition share of 0.0% is at or below the 5.4% statewide average.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Cassia County a Bridge Condition Exposure Score of 93/100 (A). The county has 117 bridges in the National Bridge Inventory, including 0 in poor condition and 4 rated scour-critical. Poor-condition bridges carry about 0 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 | 0.0% | 0.0 |
| Poor-condition traffic exposure | 25 | 0.0% of measured traffic | 0.0 |
| Scour-critical bridge share | 20 | 3.4% | 6.8 |
| Average age vs national baseline | 10 | 41 years vs 48 nationally | 0.0 |
| Traffic-data completeness | 5 | 292,740 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 | 0.0% |
| State Poor-Condition Share | 5.4% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 3.4% |
| Average Bridge Age | 41 years |
| Poor-Condition Traffic Exposure | 0 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Cassia County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| I 84b Sbl over Snake River;heyburn Br. | Scour-critical foundation rating | Fair | 17,000 | 1977 |
| I 84b Nbl over Snake River;heyburn Br. | Scour-critical foundation rating | Fair | 15,000 | 1955 |
| I 84 Wbl over Raft River | Scour-critical foundation rating | Fair | 5,750 | 1967 |
| I 84 Ebl over Raft River | Scour-critical foundation rating | Fair | 5,750 | 1973 |
| I 84b over Snake River;overland Br | High traffic | Fair | 26,000 | 2001 |
| I 86 Ebl over I 84 Wbl | High traffic | Good | 19,000 | 2020 |
| SH 77 over Canal | High traffic | Fair | 13,000 | 1985 |
| I 84 over Co.rd.;horse Butte Gs | High traffic | Fair | 11,500 | 1963 |
| I 84 over Juniper Rd;gs No.1 | High traffic | Fair | 11,000 | 1968 |
| I 84 over Juniper Rd;gs No.2 | High traffic | Fair | 11,000 | 1968 |
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.