Bridge conditions in Boone County, Iowa
134 inventoried bridges · 38 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Boone County has 38 bridges rated poor out of 134 inventoried, a 28.4% share that puts it well above the national rate of about 7%.
- 38 of the 134 bridges in Boone County, Iowa, are rated in poor condition (28.4%) in the 2025 National Bridge Inventory, as of .
- 38 bridges (28.4%) are rated good and 58 (43.3%) fair.
- The median Boone County bridge was built in 1962.
- The busiest poor-rated bridge is FM over Des Moines River (built 1972), carrying about 769 vehicles a day.
Good 28.4% · Fair 43.3% · Poor 28.4% of 134 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 Noah Creek | 1962 | 8,800 | Fair |
| US 30 over Honey Creek | 1962 | 8,800 | Fair |
| US 30 & 169 over East Beaver Creek | 1962 | 5,900 | Good |
| Ia 17 over Big Creek | 1961 | 5,300 | Fair |
| Ia 17 over US 30 | 1968 | 4,960 | Fair |
| US 30 EB over Des Moines River | 1963 | 4,400 | Fair |
| US 30 WB over Des Moines River | 1963 | 4,350 | Fair |
| US 30 over Beaver Creek | 2008 | 3,950 | Good |
| US 30 over Middle Beaver Creek | 2016 | 3,950 | Good |
| US 169 over US 30 | 1971 | 3,570 | 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 Boone County → - all 134, 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.