Ill 121 over Deer Creek
Logan County, Illinois · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ill 121 over Deer Creek in Logan County, Illinois, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 1999, making it 26 years old at the 2025 inventory.
- It carries about 3,650 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 82 of the 292 inventoried bridges in Logan County rated good (28.1%); 27 (9.2%) 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 2021, on a 48-month routine inspection cycle.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (40.11985, -89.3354)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 8 | 8 | Very good condition |
| Substructure | 8 | 8 | Very good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 230 ft |
| Location | 1.3MI SE Lincoln |
| NBI structure number | 054010600000000 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 2021 |
| Inspection interval (item 91) | 48 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 Logan County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-55 over Hurlbut Creek | 1974 | 34,900 | Fair |
| I 55 & E&w Fr Rds over Wolf Creek | 1944 | 33,125 | Fair |
| I-55 over Drainage Ditch | 1974 | 32,400 | Fair |
| I-55 over Clear Creek | 1976 | 21,600 | Fair |
| I-55 over Drainage Ditch | 1974 | 21,500 | Fair |
| I-55 over Trib Lake Fork | 1922 | 17,450 | Fair |
All bridges nearby: Logan County, IL bridge conditions · every bridge in Logan County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.