St. Clair County Bridge Report Card
St. Clair County scores 44 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
St. Clair County, Missouri
St. Clair County has 139 bridges in the National Bridge Inventory, with 27 rated poor and 5 rated scour-critical. Its poor-condition share of 19.4% is above the 8.8% statewide average. Poor-condition bridges carry about 19,197 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives St. Clair County a Bridge Condition Exposure Score of 44/100 (F). The county has 139 bridges in the National Bridge Inventory, including 27 in poor condition and 5 rated scour-critical. Poor-condition bridges carry about 19,197 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 | 19.4% | 38.8 |
| Poor-condition traffic exposure | 25 | 11.2% of measured traffic | 8.4 |
| Scour-critical bridge share | 20 | 3.6% | 7.2 |
| Average age vs national baseline | 10 | 53 years vs 48 nationally | 2.1 |
| Traffic-data completeness | 5 | 171,477 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 | 19.4% |
| State Poor-Condition Share | 8.8% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 3.6% |
| Average Bridge Age | 53 years |
| Poor-Condition Traffic Exposure | 19,197 vehicles/day |
Bridges to Watch
Top Bridges to Watch in St. Clair County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| County RD SE 650 over S Fk Weaubleau CR | Poor condition + traffic exposure | Poor | 30 | 1960 |
| County RD NE 230 over Bear CR | Poor condition + traffic exposure | Poor | 25 | 1960 |
| County RD SW 76 over Baker Br | Poor condition + traffic exposure | Poor | 20 | 1930 |
| County RD SE 750 over W Coon CR | Poor condition + traffic exposure | Poor | 20 | 1940 |
| County RD NW 1301 over Trib Of Monegaw CR | Poor condition + traffic exposure | Poor | 15 | 1930 |
| Mo 13 N over Otter CR | Poor condition + traffic exposure | Poor | 8,984 | 1963 |
| Mo 13 N over Brush CR | Poor condition + traffic exposure | Poor | 5,727 | 1962 |
| Mo 82 E over Lit Clear CR | Poor condition + traffic exposure | Poor | 971 | 1991 |
| Mo 82 E over Bear CR | Poor condition + traffic exposure | Poor | 803 | 1978 |
| RT C E over Big Muddy CR | Poor condition + traffic exposure | Poor | 763 | 1976 |
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.