US 6 & Ia 21 over Rock Creek
Poweshiek County, Iowa · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 6 & Ia 21 over Rock Creek in Poweshiek County, Iowa, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1956, making it 69 years old at the 2025 inventory.
- It carries about 1,640 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 82 of the 243 inventoried bridges in Poweshiek County rated fair (33.7%); 95 (39.1%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: deck 5 to 6, superstructure 5 to 6.
- Its most recent inspection on record is dated May 2024, on a 24-month routine inspection cycle.
- 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 → (41.74661, -92.34352)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 6 | Satisfactory condition |
| Superstructure | 5 | 6 | Satisfactory condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 126 ft |
| Location | 0.7 Mi E of W Jct Ia 21 |
| NBI structure number | 000000000045770 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | May 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Iowa department of transportation.
Busiest bridges in Poweshiek County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-80 over N.fk. English River | 1963 | 28,500 | Fair |
| I-80 over No Fork English River | 1963 | 28,500 | Fair |
| EB I-80 over 50TH Street | 1963 | 14,250 | Fair |
| I 80 WB over UP RR | 2023 | 14,000 | Good |
| WB I-80 over 50TH Street | 1963 | 14,000 | Fair |
| EB I-80 over SR V18 | 1963 | 13,600 | Fair |
All bridges nearby: Poweshiek County, IA bridge conditions · every bridge in Poweshiek County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.