Miami County Bridge Report Card
Miami County scores 88 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Miami County, Ohio
Miami County has 312 bridges in the National Bridge Inventory, with 18 rated poor and 0 rated scour-critical. Its poor-condition share of 5.8% is above the 4.7% statewide average. Poor-condition bridges carry about 16,751 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Miami County a Bridge Condition Exposure Score of 88/100 (B). The county has 312 bridges in the National Bridge Inventory, including 18 in poor condition and 0 rated scour-critical. Poor-condition bridges carry about 16,751 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 | 5.8% | 11.5 |
| Poor-condition traffic exposure | 25 | 0.9% of measured traffic | 0.7 |
| Scour-critical bridge share | 20 | 0.0% | 0.0 |
| Average age vs national baseline | 10 | 42 years vs 48 nationally | 0.0 |
| Traffic-data completeness | 5 | 1,886,391 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 | 5.8% |
| State Poor-Condition Share | 4.7% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 0.0% |
| Average Bridge Age | 42 years |
| Poor-Condition Traffic Exposure | 16,751 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Miami County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Kessler-frederick over Stoner Ditch | Poor condition + traffic exposure | Poor | 3,227 | 1954 |
| Swailes over Boone Creek | Poor condition + traffic exposure | Poor | 2,062 | 1961 |
| Swailes over Boone Creek | Poor condition + traffic exposure | Poor | 2,062 | 1963 |
| Piqua-lockington over Miami River | Poor condition + traffic exposure | Poor | 1,373 | 1972 |
| Range Line over Brush Creek | Poor condition + traffic exposure | Poor | 1,244 | 1962 |
| Fenner over Possum Run | Poor condition + traffic exposure | Poor | 1,077 | 1941 |
| Sodom-ballou North over A J Allen Ditch | Poor condition + traffic exposure | Poor | 797 | 1955 |
| Casstown-sidney over Middle Branch Lost Creek | Poor condition + traffic exposure | Poor | 797 | 1961 |
| Casstown-sidney over Little Lost Creek | Poor condition + traffic exposure | Poor | 797 | 1963 |
| Snyder over West Branch Lost Creek | Poor condition + traffic exposure | Poor | 797 | 1979 |
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.