US Bridges

Il 171 SB over Joliet Rd&bn RR Spur

Poor

Cook County, Illinois · 0.5 M NW I-55 · Structure no. 016100500000000

Built
1964
61 years old, rebuilt 1994
Condition
Poor
inspected April 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
405 ft
6 main spans
Daily traffic
40,100
2023 count
Owner
State
State Highway Agency

About this bridge

Il 171 SB over Joliet Rd&bn RR Spur is a steel stringer/multi-beam or girder carrying Il 171 SB over Joliet Rd&bn RR Spur in Cook County, Illinois. It was built in 1964 and reconstructed in 1994, so it is 61 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 3 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 40,100 vehicles a day, roughly 9% of them trucks, projected to reach 19,443 by 2046. The structure is 405 ft (123.5 m) long and 39 ft wide.

Location

Open in Google Maps
CarriesIl 171 SB
CrossesJoliet Rd&bn RR Spur
Location0.5 M NW I-55
RouteState Highway 171
CountyCook County
StateIllinois
Coordinates41.79911, -87.83304
Functional classUrban Other Principal Arterial

Condition and inspection

Poor

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.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Substructure7 GoodSome minor problems.
Last inspectionApril 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.8 US tons
Inventory rating31.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length405 ft (123.5 m)
Longest span82 ft (25.1 m)
Deck width39 ft (11.9 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40,100 (2023)
Projected traffic19,443 by 2046
Trucks9%
Lanes on structure2
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway and railroad
Detour if closed—
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 171 SB over Joliet Rd&bn RR Spur built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 1994.

What condition is Il 171 SB over Joliet Rd&bn RR Spur 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 April 2024.

How much traffic does Il 171 SB over Joliet Rd&bn RR Spur carry?

About 40,100 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is Il 171 SB over Joliet Rd&bn RR Spur?

The structure is 405 ft (123.5 m) long with a longest span of 82 ft (25.1 m) and a deck 39 ft wide.

Who owns Il 171 SB over Joliet Rd&bn RR Spur?

It is owned by the State Highway Agency.