Marion County Bridge Report Card
Marion County scores 67 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Marion County, Iowa
Marion County has 217 bridges in the National Bridge Inventory, with 28 rated poor and 3 rated scour-critical. Its poor-condition share of 12.9% is at or below the 18.6% statewide average. Poor-condition bridges carry about 10,216 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Marion County a Bridge Condition Exposure Score of 67/100 (D). The county has 217 bridges in the National Bridge Inventory, including 28 in poor condition and 3 rated scour-critical. Poor-condition bridges carry about 10,216 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 | 12.9% | 25.8 |
| Poor-condition traffic exposure | 25 | 5.6% of measured traffic | 4.2 |
| Scour-critical bridge share | 20 | 1.4% | 2.8 |
| Average age vs national baseline | 10 | 42 years vs 48 nationally | 0.0 |
| Traffic-data completeness | 5 | 181,032 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 | 12.9% |
| State Poor-Condition Share | 18.6% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 1.4% |
| Average Bridge Age | 42 years |
| Poor-Condition Traffic Exposure | 10,216 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Marion County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Local over Stream | Poor condition + traffic exposure | Poor | 62 | 1958 |
| Local over Hawk Run | Poor condition + traffic exposure | Poor | 11 | 1925 |
| Ag And Dnr Traffic over Prairie Creek | Poor condition + traffic exposure | Poor | 1 | 1952 |
| FM over English Creek | Poor condition + traffic exposure | Poor | 2,640 | 1975 |
| FM over Bnsf Rr And Stream | Poor condition + traffic exposure | Poor | 2,620 | 1964 |
| Main ST over Over Up Rr | Poor condition + traffic exposure | Poor | 1,210 | 1940 |
| FM over Long Branch Creek | Poor condition + traffic exposure | Poor | 880 | 1967 |
| FM over Competine Creek | Poor condition + traffic exposure | Poor | 710 | 1967 |
| G76 over Small Stream | Poor condition + traffic exposure | Poor | 500 | 1964 |
| G76 over Small Stream | Poor condition + traffic exposure | Poor | 400 | 1964 |
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.