Ill 138 over Cahokia Creek
Macoupin County, Illinois · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ill 138 over Cahokia Creek in Macoupin County, Illinois, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1992, making it 33 years old at the 2025 inventory.
- It carries about 2,700 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 111 of the 240 inventoried bridges in Macoupin County rated fair (46.2%); 40 (16.7%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated September 2023, 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 → (39.07884, -89.78198)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 125 ft |
| Location | 1.9MI W Jct Fai 55 |
| NBI structure number | 059005400000000 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | September 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Illinois department of transportation.
Busiest bridges in Macoupin County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Fai 55 SB over Tr 439 | 1973 | 15,200 | Fair |
| Fai 55 NB over Tr 439 | 1973 | 15,200 | Fair |
| Ill 108 over Drainage Ditch | 1933 | 6,950 | Fair |
| Ill 4 over East Fork Creek | 1957 | 4,800 | Fair |
| Il 111 over Little Piasa Creek | 1929 | 4,550 | Fair |
| Il 111 over S Br Little Piasa CR | 1929 | 4,550 | Fair |
All bridges nearby: Macoupin County, IL bridge conditions · every bridge in Macoupin County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.