US Bridges

I-55 (nb) over Illinois Central RR

Good

Sangamon County, Illinois · .3M N Il 54/SANG. Av · Structure no. 084001700000000

Built
1963
62 years old, rebuilt 1995
Condition
Good
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
244 ft
3 main spans
Daily traffic
14,600
2023 count
Owner
State
State Highway Agency

About this bridge

I-55 (nb) over Illinois Central RR is a steel continuous stringer/multi-beam or girder carrying I-55 (nb) over Illinois Central RR in Sangamon County, Illinois. It was built in 1963 and reconstructed in 1995, 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 good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 14,600 vehicles a day, roughly 31% of them trucks, projected to reach 13,787 by 2046. The structure is 244 ft (74.5 m) long and 65 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-55 (nb)
CrossesIllinois Central RR
Location.3M N Il 54/SANG. Av
RouteInterstate 55
CountySangamon County
StateIllinois
Coordinates39.83553, -89.59329
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.8 US tons
Inventory rating42.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length244 ft (74.5 m)
Longest span93 ft (28.3 m)
Deck width65 ft (19.9 m)
Roadway width62 ft (19 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic14,600 (2023)
Projected traffic13,787 by 2046
Trucks31%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-55 (nb) over Illinois Central RR built?

It was built in 1963, making it 62 years old in 2025. It was reconstructed in 1995.

What condition is I-55 (nb) over Illinois Central RR in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2024.

How much traffic does I-55 (nb) over Illinois Central RR carry?

About 14,600 vehicles per day (2023 count), of which roughly 31% are trucks.

How long is I-55 (nb) over Illinois Central RR?

The structure is 244 ft (74.5 m) long with a longest span of 93 ft (28.3 m) and a deck 65 ft wide.

Who owns I-55 (nb) over Illinois Central RR?

It is owned by the State Highway Agency.