Bridge conditions in Louisa County, Iowa
151 inventoried bridges · 22 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Of the 151 Louisa County bridges in the federal inventory, 22 carry a poor rating. That 14.6% share is roughly 2x the national average.
- 22 of the 151 bridges in Louisa County, Iowa, are rated in poor condition (14.6%) in the 2025 National Bridge Inventory, as of .
- 48 bridges (31.8%) are rated good and 81 (53.6%) fair.
- The median Louisa County bridge was built in 1983.
- The busiest poor-rated bridge is Linn St over Indian Creek (built 1986), carrying about 780 vehicles a day.
Good 31.8% · Fair 53.6% · Poor 14.6% of 151 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.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Linn St over Indian Creek | 1986 | 780 | Poor |
| FM over Small Stream | 1960 | 660 | Poor |
| FM over Sm Stream | 1950 | 490 | Poor |
| FM over Long Creek | 1963 | 250 | Poor |
| Manor Rd over Drainage | 1920 | 144 | Poor |
| FM over Otter CR | 1959 | 80 | Poor |
| Local over Indian Creek | 1969 | 62 | Poor |
| Local over Small Stream | 1974 | 51 | Poor |
| Local over Small Stream | 1943 | 47 | Poor |
| FM over Small Stream | 1972 | 45 | Poor |
| FM over Otter Creek | 1955 | 35 | Poor |
| Local over Small Stream | 1960 | 35 | Poor |
| Local over Otter Creek | 1920 | 30 | Poor |
| Local over Short Creek | 1964 | 26 | Poor |
| Local over Stream | 1920 | 21 | Poor |
| Local over Stream | 1915 | 21 | Poor |
| Local over Otter CR | 1921 | 16 | Poor |
| Local over Small Stream | 1920 | 11 | Poor |
| Local over Small Stream | 1930 | 11 | Poor |
| V Ave over Buffington Creek | 1893 | 11 | Poor |
| Local over Small Stream | 1930 | 11 | Poor |
| Local over Small Stream | 1950 | 11 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 61 over Millrace Creek | 1985 | 4,950 | Fair |
| US 61 over Overflow Iowa River | 1985 | 4,950 | Fair |
| US 61 over Overflow Iowa River | 1985 | 4,950 | Fair |
| US 61 over Overflow Iowa River | 1985 | 4,950 | Fair |
| US 61 over Muskrat Lake | 1985 | 4,950 | Fair |
| US 61 over Iowa River | 1980 | 4,950 | Fair |
| US 61 over Honey Creek | 1997 | 4,420 | Good |
| US 61 over Drainage Ditch | 1985 | 4,420 | Fair |
| Ia 92 over Monkey Run Creek | 1984 | 4,240 | Fair |
| Ia 92 over Iowa River | 1985 | 4,090 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
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.