US Bridges

I-355 NB over I-55

Fair

Will County, Illinois · 1.3M S of Boughton · Structure no. 099994400000000

Built
1989
36 years old
Condition
Fair
inspected April 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
360 ft
2 main spans
Daily traffic
41,950
2023 count
Owner
Toll Authority
State Toll Authority

About this bridge

I-355 NB over I-55 is a steel stringer/multi-beam or girder carrying I-355 NB over I-55 in Will County, Illinois. It was built in 1989, so it is 36 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 41,950 vehicles a day, roughly 16% of them trucks, projected to reach 47,448 by 2046. The structure is 360 ft (109.7 m) long and 63 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesI-355 NB
CrossesI-55
Location1.3M S of Boughton
RouteInterstate 355
CountyWill County
StateIllinois
Coordinates41.70423, -88.03088
Functional classUrban Principal Arterial - Interstate

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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating68.2 US tons
Inventory rating38.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadUnknown
Structure length360 ft (109.7 m)
Longest span180 ft (54.9 m)
Deck width63 ft (19.2 m)
Roadway width59 ft (18 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic41,950 (2023)
Projected traffic47,448 by 2046
Trucks16%
Lanes on structure4
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a toll road
National Highway SystemYes
Strategic Highway NetworkNon-Interstate STRAHNET route

Ownership and planned work

OwnerState Toll Authority
Maintained byState Toll Authority
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-355 NB over I-55 built?

It was built in 1989, making it 36 years old in 2025.

What condition is I-355 NB 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 April 2024.

How much traffic does I-355 NB over I-55 carry?

About 41,950 vehicles per day (2023 count), of which roughly 16% are trucks.

How long is I-355 NB over I-55?

The structure is 360 ft (109.7 m) long with a longest span of 180 ft (54.9 m) and a deck 63 ft wide.

Who owns I-355 NB over I-55?

It is owned by the State Toll Authority.