Ill 34 & Ill 146 over Threemile Creek
Hardin County, Illinois · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ill 34 & Ill 146 over Threemile Creek in Hardin County, Illinois, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 2009, making it 16 years old at the 2025 inventory.
- It carries about 1,550 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 22 of the 61 inventoried bridges in Hardin County rated fair (36.1%); 4 (6.6%) 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 48-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 → (37.45983, -88.37704)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 8 | 8 | Very good condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 67 ft |
| Location | 1.5 Mi E of Ill 146 |
| NBI structure number | 035001500000000 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | September 2023 |
| 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 Hardin County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Ill 146 over Big Creek | 2004 | 1,900 | Good |
| Ill 146 over Hosick Creek | 1953 | 1,500 | Poor |
| Ill 146 over Peters Creek | 2013 | 1,500 | Good |
| Ill 146 over Stream | 1954 | 1,500 | Good |
| Ill 34 over Rose Creek | 1924 | 1,400 | Fair |
| Ill 34 over Pinhook Creek | 1924 | 1,200 | Fair |
All bridges nearby: Hardin County, IL bridge conditions · every bridge in Hardin County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.