Tr 49 B over Prairie CR
Iroquois County, Illinois · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Tr 49 B over Prairie CR in Iroquois County, Illinois, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 1 (imminent failure condition) on the 0-9 scale.
- It was built in 1904, making it 121 years old at the 2025 inventory.
- It carries about 25 vehicles a day (traffic count year 2022).
- Its listed owner is a town or township highway agency.
- It is one of 83 of the 568 inventoried bridges in Iroquois County rated poor (14.6%); 83 (14.6%) are rated poor.
- Its traffic status in the 2025 inventory is closed to all traffic (NBI item 41).
- Its class is unchanged from 2024 (poor), but component ratings moved: superstructure 4 to 1, substructure 4 to 1.
- Status change: newly closed since 2024.
- Its most recent inspection on record is dated December 2024, on a 24-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (40.91724, -87.82054)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 4 | 1 | Imminent failure condition |
| Substructure | 4 | 1 | Imminent failure condition |
Bridge details
| Structure | Steel through truss |
| Length | about 50 ft |
| Location | 1.5 Mi E. Lrable |
| NBI structure number | 038323000000000 |
| Condition class | Poor |
| Traffic status (item 41) | Closed to all traffic |
| Last inspection (item 90) | December 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Illinois department of transportation.
Busiest bridges in Iroquois County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-57 over Dranage Ditch | 2015 | 18,100 | Fair |
| I-57 over Dranage Ditch | 2015 | 18,100 | Fair |
| I-57 NB & SB over Prairie Creek | 2015 | 18,100 | Fair |
| Fai-57 over Stream | 1971 | 17,600 | Fair |
| I-57 SB over Langan Creek | 2013 | 9,550 | Fair |
| Fai-57 NB over Langan Creek | 2014 | 9,550 | Fair |
All bridges nearby: Iroquois County, IL bridge conditions · every bridge in Iroquois County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.