Williamson County Bridge Report Card
Williamson County scores 88 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Williamson County, Illinois
Williamson County has 200 bridges in the National Bridge Inventory, with 7 rated poor and 0 rated scour-critical. Its poor-condition share of 3.5% is at or below the 9.5% statewide average. Poor-condition bridges carry about 58,775 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Williamson County a Bridge Condition Exposure Score of 88/100 (B). The county has 200 bridges in the National Bridge Inventory, including 7 in poor condition and 0 rated scour-critical. Poor-condition bridges carry about 58,775 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 | 3.5% | 7.0 |
| Poor-condition traffic exposure | 25 | 6.8% of measured traffic | 5.1 |
| Scour-critical bridge share | 20 | 0.0% | 0.0 |
| Average age vs national baseline | 10 | 40 years vs 48 nationally | 0.0 |
| Traffic-data completeness | 5 | 867,492 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 | 3.5% |
| State Poor-Condition Share | 9.5% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 0.0% |
| Average Bridge Age | 40 years |
| Poor-Condition Traffic Exposure | 58,775 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Williamson County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Ill 13 EB over Craborchard Lake | Poor condition + traffic exposure | Poor | 25,600 | 1964 |
| Ill 13 EB over Craborchard Lake | Poor condition + traffic exposure | Poor | 23,500 | 1964 |
| Fas 903 (ch 2) over Interstate 57 | Poor condition + traffic exposure | Poor | 6,500 | 1961 |
| Tr 241 (cedar Grov over Interstate 57 | Poor condition + traffic exposure | Poor | 1,750 | 1961 |
| Tr 23 (stiritz Rd) over Interstate 57 | Poor condition + traffic exposure | Poor | 1,000 | 1961 |
| Tr 608 over Mine Haulage Road | Poor condition + traffic exposure | Poor | 250 | 1978 |
| Tr 573 over South Fork Saline R. | Poor condition + traffic exposure | Poor | 175 | 1977 |
| Ill 13 over Stream | High traffic | Good | 26,300 | 1959 |
| EB Il 13 over Bnsf Rr | High traffic | Fair | 26,300 | 2014 |
| EB Il 13 over Marathon DR | High traffic | Good | 26,300 | 2014 |
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.