Sierra County Bridge Report Card
Sierra County scores 80 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Sierra County, New Mexico
Sierra County has 112 bridges in the National Bridge Inventory, with 5 rated poor and 4 rated scour-critical. Its poor-condition share of 4.5% is above the 4.3% statewide average. Poor-condition bridges carry about 9,415 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Sierra County a Bridge Condition Exposure Score of 80/100 (B). The county has 112 bridges in the National Bridge Inventory, including 5 in poor condition and 4 rated scour-critical. Poor-condition bridges carry about 9,415 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 | 4.5% | 8.9 |
| Poor-condition traffic exposure | 25 | 2.6% of measured traffic | 1.9 |
| Scour-critical bridge share | 20 | 3.6% | 7.1 |
| Average age vs national baseline | 10 | 52 years vs 48 nationally | 1.8 |
| Traffic-data completeness | 5 | 363,590 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 | 4.5% |
| State Poor-Condition Share | 4.3% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 3.6% |
| Average Bridge Age | 52 years |
| Poor-Condition Traffic Exposure | 9,415 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Sierra County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Nm-187 over King Canyon | Poor condition + traffic exposure | Poor | 521 | 1933 |
| Nm-187 over Greenhorn Arroyo | Poor condition + traffic exposure | Poor | 297 | 1928 |
| I-25 Sbl/nbl over Unnamed Waterway | Poor condition + traffic exposure | Poor | 7,331 | 1965 |
| L-00011 over I-25 NB And SB | Poor condition + traffic exposure | Poor | 1,196 | 1968 |
| 51-b038 over Rio Grande | Poor condition + traffic exposure | Poor | 70 | 1966 |
| Nm-187 over Seco Creek | Scour-critical foundation rating | Fair | 521 | 1933 |
| Nm-152 over Percha Creek | Scour-critical foundation rating | Fair | 308 | 1961 |
| I-25 Nbl over Palomas Creek | High traffic | Fair | 8,962 | 1968 |
| I-25 Sbl over Palomas Creek | High traffic | Fair | 8,962 | 1968 |
| I-25 Nbl/sbl over Canada Honda | High traffic | Fair | 8,962 | 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.