Ill 161 over Wilken Lake
Clinton County, Illinois · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ill 161 over Wilken Lake in Clinton County, Illinois, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1935 and reconstructed in 1990, making it 90 years old at the 2025 inventory.
- It carries about 4,250 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 71 of the 190 inventoried bridges in Clinton County rated fair (37.4%); 13 (6.8%) 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 April 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 → (38.54821, -89.53194)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 398 ft |
| Location | 0.5 M E Germantown |
| NBI structure number | 014000900000000 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 2023 |
| 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 Illinois department of transportation.
Busiest bridges in Clinton County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Fai 64 over Trib to Queens Lake | 1973 | 31,000 | Good |
| Fai 64 EB over Sugar Ck Overflow | 1971 | 15,500 | Fair |
| Fai 64 WB over Sugar Ck Overflow | 1971 | 15,500 | Good |
| Fai 64 EB over Sugar Creek | 1970 | 15,500 | Fair |
| Fai 64 WB over Sugar Creek | 1970 | 15,500 | Good |
| Fai 64 EB over Sycamore Drainage Dt | 1970 | 15,500 | Good |
All bridges nearby: Clinton County, IL bridge conditions · every bridge in Clinton County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.