I-55 (nb) over Sangamon River
PoorSangamon County, Illinois · 2.8M N IL54/SANG. Av · Structure no. 084001800000000
- Built
- 1963
- 62 years old, rebuilt 1993
- Condition
- Poor
- inspected November 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 1,125 ft
- 3 main spans
- Daily traffic
- 14,600
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I-55 (nb) over Sangamon River is a steel continuous stringer/multi-beam or girder carrying I-55 (nb) over Sangamon River in Sangamon County, Illinois. It was built in 1963 and reconstructed in 1993, so it is 62 years old, older than the Illinois average of 45.3 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
It carries about 14,600 vehicles a day, roughly 31% of them trucks, projected to reach 13,787 by 2046. The structure is 1,125 ft (342.9 m) long and 47 ft wide. If it were closed, the detour would be 1.2 mi (2 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I-55 (nb) over Sangamon River built?
It was built in 1963, making it 62 years old in 2025. It was reconstructed in 1993.
What condition is I-55 (nb) over Sangamon River in?
The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in November 2024.
How much traffic does I-55 (nb) over Sangamon River carry?
About 14,600 vehicles per day (2023 count), of which roughly 31% are trucks.
How long is I-55 (nb) over Sangamon River?
The structure is 1,125 ft (342.9 m) long with a longest span of 180 ft (54.9 m) and a deck 47 ft wide.
Who owns I-55 (nb) over Sangamon River?
It is owned by the State Highway Agency.