Ia 31 over Silver Creek
Cherokee County, Iowa · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ia 31 over Silver Creek in Cherokee County, Iowa, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1950, making it 75 years old at the 2025 inventory.
- It carries about 1,180 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 90 of the 244 inventoried bridges in Cherokee County rated fair (36.9%); 68 (27.9%) 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 6 to 5.
- 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 → (42.63402, -95.57449)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 5 | Fair condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 153 ft |
| Location | 1.0 mi. W of US 59 |
| NBI structure number | 000000000019540 |
| 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 Cherokee County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 59 over Railroad Creek | 1973 | 7,200 | Fair |
| US 59 over Westcott Pk Loop | 1972 | 4,510 | Fair |
| US 59 over Little Sioux River | 1973 | 4,510 | Fair |
| W Bluff St over Railroad Creek | 1961 | 3,529 | Poor |
| Ia 3 over Fork Little Sioux River | 1979 | 3,410 | Fair |
| Ia 3 over Maple River | 1985 | 3,270 | Fair |
All bridges nearby: Cherokee County, IA bridge conditions · every bridge in Cherokee County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.