Bridge conditions in Marshall County, Iowa
303 inventoried bridges · 130 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Marshall County has 130 bridges rated poor out of 303 inventoried, a 42.9% share that puts it well above the national rate of about 7%.
- 130 of the 303 bridges in Marshall County, Iowa, are rated in poor condition (42.9%) in the 2025 National Bridge Inventory, as of .
- 100 bridges (33.0%) are rated good and 73 (24.1%) fair.
- The median Marshall County bridge was built in 1978.
- The busiest poor-rated bridge is So Center St over Linn Creek (built 1951), carrying about 10,448 vehicles a day.
Good 33.0% · Fair 24.1% · Poor 42.9% of 303 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 30 over Davisons Creek | 1954 | 14,700 | Fair |
| Ia 14 over Linn Creek | 1985 | 13,300 | Good |
| Ia 14 over UP RR Madison&market St | 1985 | 13,300 | Fair |
| So. 6TH St. over Linn Creek | 1984 | 11,300 | Fair |
| So Center St over Linn Creek | 1951 | 10,448 | Poor |
| So Center St over RR and Madison St | 1951 | 9,491 | Poor |
| Ia 330 SB over North Timber Creek | 1979 | 9,000 | Good |
| S 3RD St over UP RR & St | 1984 | 9,000 | Fair |
| Ia 330 over Drainage Ditch | 1982 | 8,300 | Good |
| Ia 330 NB over North Skunk River | 1969 | 8,300 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
Every bridge in Marshall County → - all 303, busiest first, each with its own condition record.
All of Iowa: Iowa bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.