Tr 343 over Sixmile CR Tributary
Pike County, Illinois · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Tr 343 over Sixmile CR Tributary in Pike County, Illinois, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 2 (critical condition) on the 0-9 scale.
- It was built in 1959, making it 66 years old at the 2025 inventory.
- It carries about 50 vehicles a day (traffic count year 2023).
- Its listed owner is a town or township highway agency.
- It is one of 34 of the 332 inventoried bridges in Pike County rated poor (10.2%); 34 (10.2%) 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 March 2023, on a 24-month routine inspection cycle.
- 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 → (39.53571, -90.90292)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 2 | 2 | Critical condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 36 ft |
| Location | 0.75 Mi SE Summer Hi |
| NBI structure number | 075315200000000 |
| Condition class | Poor |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | March 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 Pike County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-72 / US 36 over Miss R/bnrr/nsrr/st | 1999 | 16,500 | Poor |
| I-72 over Trib Blue Creek | 1988 | 9,900 | Good |
| I-72 over Drainage Ditch | 1988 | 9,410 | Good |
| I-72 over Drainage Ditch | 1986 | 9,400 | Fair |
| I-72 over Drainage Ditch | 1986 | 9,400 | Fair |
| I-72 / US 36 over Drainage Ditch | 1986 | 9,400 | Fair |
All bridges nearby: Pike County, IL bridge conditions · every bridge in Pike County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.