Tr 311 over Marys River
Randolph County, Illinois · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Tr 311 over Marys River in Randolph 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 1977, making it 48 years old at the 2025 inventory.
- It carries about 450 vehicles a day (traffic count year 2024).
- Its listed owner is a town or township highway agency.
- It is one of 52 of the 149 inventoried bridges in Randolph County rated fair (34.9%); 10 (6.7%) 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 March 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 → (37.91887, -89.73273)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Concrete channel beam |
| Length | about 202 ft |
| Location | 4.25 M E of Chester |
| NBI structure number | 079429200000000 |
| Condition class | Fair |
| 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 Randolph County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Il 3 over Black Creek | 1995 | 8,400 | Good |
| Ill 150 over Miss Riv/fau 9416 | 1942 | 6,250 | Poor |
| Il 3 over UPRR | 1971 | 5,650 | Good |
| Il 3 over Nine Mile Creek | 2024 | 5,650 | Good |
| Ill 4-150 over Marys River | 1928 | 5,500 | Fair |
| Il 150 over Little Marys River | 1999 | 5,450 | Good |
All bridges nearby: Randolph County, IL bridge conditions · every bridge in Randolph County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.