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, Kansas
Miami County has 327 bridges in the National Bridge Inventory, with 10 rated poor and 7 rated scour-critical. Its poor-condition share of 3.1% is at or below the 5.2% statewide average. Poor-condition bridges carry about 1,138 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 327 bridges in the National Bridge Inventory, including 10 in poor condition and 7 rated scour-critical. Poor-condition bridges carry about 1,138 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 | 3.1% | 6.1 |
| Poor-condition traffic exposure | 25 | 0.2% of measured traffic | 0.2 |
| Scour-critical bridge share | 20 | 2.1% | 4.3 |
| Average age vs national baseline | 10 | 51 years vs 48 nationally | 1.5 |
| Traffic-data completeness | 5 | 530,206 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 | 3.1% |
| State Poor-Condition Share | 5.2% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 2.1% |
| Average Bridge Age | 51 years |
| Poor-Condition Traffic Exposure | 1,138 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Miami County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| 311th Street over Trib. Marais Des Cygnes | Poor condition + traffic exposure | Poor | 30 | 1918 |
| Woodland Road over Trib. To Sweetwater Crk | Poor condition + traffic exposure | Poor | 655 | 2005 |
| 255th Street over Stream | Poor condition + traffic exposure | Poor | 102 | 1965 |
| 399th ST over La Cygne Lake | Poor condition + traffic exposure | Poor | 95 | 1962 |
| New Lancaster RD over Trib. To Middle Creek | Poor condition + traffic exposure | Poor | 94 | 1920 |
| 239th Street over Trib. To Rock Creek | Poor condition + traffic exposure | Poor | 48 | 1915 |
| 267th Street over Trib. To Ten Mile Creek | Poor condition + traffic exposure | Poor | 48 | 1920 |
| 351st Street over Middle Creek | Poor condition + traffic exposure | Poor | 35 | 1920 |
| 319th Street over Trib. Marais Des Cygnes | Poor condition + traffic exposure | Poor | 17 | 1993 |
| 323rd Street over Trib. Marais Des Cygnes | Poor condition + traffic exposure | Poor | 14 | 1930 |
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.