Bridge conditions in Harrison County, Iowa
222 inventoried bridges · 41 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
About one in 5 bridges in Harrison County is rated in poor condition: 41 of 222 on the federal inventory, one of the higher shares in Iowa.
- 41 of the 222 bridges in Harrison County, Iowa, are rated in poor condition (18.5%) in the 2025 National Bridge Inventory, as of .
- 61 bridges (27.5%) are rated good and 120 (54.1%) fair.
- The median Harrison County bridge was built in 1968.
- The busiest poor-rated bridge is FM Easton Trail over Allen Creek (built 1969), carrying about 335 vehicles a day.
Good 27.5% · Fair 54.1% · Poor 18.5% of 222 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 |
|---|---|---|---|
| FM Easton Trail over Allen Creek | 1969 | 335 | Poor |
| FM Laredo Ave over Allen Creek | 1942 | 139 | Poor |
| L23 Laredo Ave over Steer Creek | 1942 | 139 | Poor |
| 8TH Street over Boyer River | 1900 | 123 | Poor |
| FM - 335TH St over Mosquito Creek | 1920 | 120 | Poor |
| FM Tabor Ave over Small Stream | 1956 | 110 | Poor |
| Loc Canal St over Willow River | 1916 | 100 | Poor |
| Medford Ave over Willow River | 1900 | 89 | Poor |
| Loc 128 Trail over Boyer River | 1940 | 89 | Poor |
| 198TH St over Small Creek | 1950 | 79 | Poor |
| FM & 155TH St over Mud Creek | 1940 | 79 | Poor |
| FM - 335TH St over Small Creek | 1952 | 71 | Poor |
| Vienna Ave over Pigeon Creek | 1967 | 60 | Poor |
| Jasper Trail over Small Creek | 1900 | 50 | Poor |
| Local Taylor Av over Small Creek | 1955 | 45 | Poor |
| Neely Trail over Willow Creek | 1940 | 45 | Poor |
| Taylor Ave over Pigeon Creek | 1920 | 40 | Poor |
| Local 120TH St over Little Sioux River | 1971 | 40 | Poor |
| 288TH St over Mosquito Creek | 1940 | 34 | Poor |
| Toledo Ave over Pigeon Creek | 1951 | 34 | Poor |
| 242ND Trail over Drainage Ditch | 2013 | 34 | Poor |
| Parker Trail over Small Creek | 1916 | 29 | Poor |
| Mobile Ave over Hoffman Creek | 1940 | 29 | Poor |
| Loc 215TH St over Pigeon Creek | 1955 | 26 | Poor |
| 280TH St over Mosquito Creek | 1940 | 20 | Poor |
| 305TH St over Keg Creek | 1957 | 20 | Poor |
| 315TH St over Mosquito Creek | 1930 | 20 | Poor |
| Loc 335TH St over Allen Creek | 1959 | 20 | Poor |
| FM & Nash Trail over Allen Creek | 1976 | 20 | Poor |
| 240TH Street over Pigeon Creek | 1967 | 15 | Poor |
| 180TH St over Willow Creek | 1975 | 15 | Poor |
| 325TH St over Keg Creek | 1900 | 11 | Poor |
| 325TH St over Pigeon Creek | 1960 | 11 | Poor |
| Reno Ave over Six Mile Creek | 1930 | 11 | Poor |
| 250TH St over Allen Creek | 1965 | 11 | Poor |
| Loc 210TH St over Little Pigeon | 1930 | 11 | Poor |
| 155TH St over Willow River | 1930 | 11 | Poor |
| Mobile Ave over Allen Creek | 1957 | 11 | Poor |
| 185TH Lane over Allen Creek | 1986 | 5 | Poor |
| Kendall Trail over Steer Creek | 1969 | 5 | Poor |
| 125TH St over Small Stream | 1960 | 5 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 30 over Willow Creek | 1972 | 10,300 | Fair |
| US 30 over UPRR | 1998 | 10,300 | Good |
| NB I-29 over Boyer River | 1958 | 10,050 | Fair |
| SB I-29 over Boyer River | 1958 | 10,050 | Fair |
| SB I-29 over over UP RR | 1967 | 7,750 | Fair |
| NB I-29 over Allen Creek | 1967 | 7,750 | Fair |
| SB I-29 over Allen Creek | 1967 | 7,750 | Fair |
| NB I-29 over UP RR & K-45 | 1967 | 7,600 | Fair |
| SB I-29 over UP RR & K-45 | 1967 | 7,600 | Fair |
| NB I-29 over Old Soldier River Ditch | 1967 | 7,600 | 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.