US Bridges

Chicago RD over I-39 & US 51

Fair

Lee County, Illinois · 4.8 MI S of US 30 · Structure no. 052005500000000

Built
1983
42 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
306 ft
2 main spans
Daily traffic
950
2022 count
Owner
State
State Highway Agency

About this bridge

Chicago RD over I-39 & US 51 is a steel continuous stringer/multi-beam or girder carrying Chicago RD over I-39 & US 51 in Lee County, Illinois. It was built in 1983, so it is 42 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 5 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 950 vehicles a day, roughly 15% of them trucks, projected to reach 1,010 by 2046. The structure is 306 ft (93.3 m) long and 64 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesChicago RD
CrossesI-39 & US 51
Location4.8 MI S of US 30
RouteCounty Highway 0
CountyLee County
StateIllinois
Coordinates41.69856, -89.03134
Functional classRural Major Collector

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56.8 US tons
Inventory rating34 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20 + Mod
Structure length306 ft (93.3 m)
Longest span131 ft (39.8 m)
Deck width64 ft (19.5 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic950 (2022)
Projected traffic1,010 by 2046
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

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 Chicago RD over I-39 & US 51 built?

It was built in 1983, making it 42 years old in 2025.

What condition is Chicago RD over I-39 & US 51 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 July 2023.

How much traffic does Chicago RD over I-39 & US 51 carry?

About 950 vehicles per day (2022 count), of which roughly 15% are trucks.

How long is Chicago RD over I-39 & US 51?

The structure is 306 ft (93.3 m) long with a longest span of 131 ft (39.8 m) and a deck 64 ft wide.

Who owns Chicago RD over I-39 & US 51?

It is owned by the State Highway Agency.