US Bridges

Il 4 over Macoupin Creek

Fair

Macoupin County, Illinois · 1.7M S Il 108 · Structure no. 059000700000000

Built
1960
65 years old, rebuilt 2001
Condition
Fair
inspected December 2021
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
362 ft
5 main spans
Daily traffic
4,450
2023 count
Owner
State
State Highway Agency

About this bridge

Il 4 over Macoupin Creek is a steel continuous stringer/multi-beam or girder carrying Il 4 over Macoupin Creek in Macoupin County, Illinois. It was built in 1960 and reconstructed in 2001, so it is 65 years old, older 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 4,450 vehicles a day, roughly 5% of them trucks, projected to reach 4,242 by 2046. The structure is 362 ft (110.2 m) long and 39 ft wide. If it were closed, the detour would be 16.8 mi (27 km).

Location

Open in Google Maps
CarriesIl 4
CrossesMacoupin Creek
Location1.7M S Il 108
RouteState Highway 4
CountyMacoupin County
StateIllinois
Coordinates39.25973, -89.84966
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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionDecember 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating98.2 US tons
Inventory rating61.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length362 ft (110.2 m)
Longest span80 ft (24.5 m)
Deck width39 ft (11.8 m)
Roadway width35 ft (10.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,450 (2023)
Projected traffic4,242 by 2046
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.8 mi (27 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Il 4 over Macoupin Creek built?

It was built in 1960, making it 65 years old in 2025. It was reconstructed in 2001.

What condition is Il 4 over Macoupin Creek 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 2021.

How much traffic does Il 4 over Macoupin Creek carry?

About 4,450 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is Il 4 over Macoupin Creek?

The structure is 362 ft (110.2 m) long with a longest span of 80 ft (24.5 m) and a deck 39 ft wide.

Who owns Il 4 over Macoupin Creek?

It is owned by the State Highway Agency.