Ia 1 over Middle Walnut Creek
Jefferson County, Iowa · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ia 1 over Middle Walnut Creek in Jefferson County, Iowa, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1969, making it 56 years old at the 2025 inventory.
- It carries about 2,560 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 55 of the 156 inventoried bridges in Jefferson County rated fair (35.3%); 31 (19.9%) are rated poor.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (41.13189, -91.96605)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 7 | Good condition |
| Substructure | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 123 ft |
| Location | 3.2 mi. S of S Jct. IA 78 |
| NBI structure number | 000000000031410 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Iowa department of transportation.
Busiest bridges in Jefferson County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 34 EB over BNSF RR | 2008 | 7,800 | Good |
| US 34 WB over BNSF RR | 2008 | 7,800 | Good |
| US 34 over Mitchell Creek | 2009 | 4,360 | Good |
| Ia 1 over Crow Creek | 1928 | 4,100 | Fair |
| US 34 EB over Big Cedar Creek | 2016 | 3,900 | Fair |
| US 34 WB over Big Cedar Creek | 2006 | 3,900 | Good |
All bridges nearby: Jefferson County, IA bridge conditions · every bridge in Jefferson County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.