US 218 over Big Slough Creek
Washington County, Iowa · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 218 over Big Slough Creek in Washington County, Iowa, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 7 (good condition) on the 0-9 scale.
- It was built in 1997, making it 28 years old at the 2025 inventory.
- It carries about 12,400 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 82 of the 207 inventoried bridges in Washington County rated good (39.6%); 33 (15.9%) are rated poor.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (41.23717, -91.53264)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 7 | Good condition |
Bridge details
| Structure | Continuous concrete culvert |
| Length | about 37 ft |
| Location | 3.8 Mi. S of Jct. Ia 92 |
| NBI structure number | 000000000606880 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Iowa department of transportation.
Busiest bridges in Washington County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 218 over Whiskey Run Creek | 1984 | 14,900 | Fair |
| US 218 over Stream | 1984 | 14,900 | Fair |
| US 218 over Drainage | 1997 | 13,800 | Good |
| SB US 218 over Goose Creek | 1984 | 7,600 | Fair |
| SB US 218 over Davis Creek | 1984 | 7,600 | Fair |
| US 218 SB over English River | 1984 | 7,600 | Fair |
All bridges nearby: Washington County, IA bridge conditions · every bridge in Washington County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.