US Bridges

Il 47 over I-55

Fair

Grundy County, Illinois · IL47/I-55INTERCHANGE · Structure no. 032012500000000

Built
2022
3 years old
Condition
Fair
inspected December 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
247 ft
2 main spans
Daily traffic
3,600
2023 count
Owner
State
State Highway Agency

About this bridge

Il 47 over I-55 is a steel continuous stringer/multi-beam or girder carrying Il 47 over I-55 in Grundy County, Illinois. It was built in 2022, so it is 3 years old, younger than the Illinois average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 3,600 vehicles a day, roughly 25% of them trucks, projected to reach 11,040 by 2046. The structure is 247 ft (75.4 m) long and 93 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesIl 47
CrossesI-55
LocationIL47/I-55INTERCHANGE
RouteState Highway 47
CountyGrundy County
StateIllinois
Coordinates41.11732, -88.41404
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation8: Equal to present desirable criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment9: Superior to present desirable criteria
Operating rating62.2 US tons
Inventory rating47.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 25 or greater
Structure length247 ft (75.4 m)
Longest span122 ft (37.2 m)
Deck width93 ft (28.3 m)
Roadway width72 ft (21.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,600 (2023)
Projected traffic11,040 by 2046
Trucks25%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

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 Il 47 over I-55 built?

It was built in 2022, making it 3 years old in 2025.

What condition is Il 47 over I-55 in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in December 2024.

How much traffic does Il 47 over I-55 carry?

About 3,600 vehicles per day (2023 count), of which roughly 25% are trucks.

How long is Il 47 over I-55?

The structure is 247 ft (75.4 m) long with a longest span of 122 ft (37.2 m) and a deck 93 ft wide.

Who owns Il 47 over I-55?

It is owned by the State Highway Agency.