Prophetstown Road over Spring Slough
Whiteside County, Illinois · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Prophetstown Road over Spring Slough in Whiteside County, Illinois, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1947, making it 78 years old at the 2025 inventory.
- It carries about 2,100 vehicles a day (traffic count year 2021).
- Its listed owner is the county highway agency.
- It is one of 201 of the 278 inventoried bridges in Whiteside County rated fair (72.3%); 23 (8.3%) 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 → (41.7481, -89.76368)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 6 | Satisfactory condition |
Bridge details
| Structure | Steel culvert |
| Length | about 23 ft |
| Location | 3 Mi SW of Rock Fall |
| NBI structure number | 098303600000000 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Illinois department of transportation.
Busiest bridges in Whiteside County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Il 40 over Rock River | 2012 | 19,800 | Good |
| I-88 over Ditch | 1975 | 13,100 | Good |
| Fai 88 over Stream | 1975 | 12,600 | Fair |
| I-88 over Ditch | 1975 | 12,500 | Good |
| I-88 over Ditch | 1975 | 12,500 | Good |
| Il 40 Locust St over Stream | 1987 | 11,100 | Good |
All bridges nearby: Whiteside County, IL bridge conditions · every bridge in Whiteside County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.