US Bridges

I-72 (eb) over FA320 (IL-121) & Cn RR

Poor

Macon County, Illinois · 1.5 MI NW Decatur · Structure no. 058007400000000

Built
1976
49 years old
Condition
Poor
inspected December 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
267 ft
3 main spans
Daily traffic
6,400
2023 count
Owner
State
State Highway Agency

About this bridge

I-72 (eb) over FA320 (IL-121) & Cn RR is a steel continuous stringer/multi-beam or girder carrying I-72 (eb) over FA320 (IL-121) & Cn RR in Macon County, Illinois. It was built in 1976, so it is 49 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 4 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 6,400 vehicles a day, roughly 29% of them trucks, projected to reach 6,565 by 2046. The structure is 267 ft (81.5 m) long and 62 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-72 (eb)
CrossesFA320 (IL-121) & Cn RR
Location1.5 MI NW Decatur
RouteInterstate 72
CountyMacon County
StateIllinois
Coordinates39.8942, -89.00679
Functional classUrban Principal Arterial - Interstate

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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionDecember 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.3 US tons
Inventory rating38.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length267 ft (81.5 m)
Longest span124 ft (37.9 m)
Deck width62 ft (19 m)
Roadway width59 ft (17.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,400 (2023)
Projected traffic6,565 by 2046
Trucks29%
Lanes on structure3
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway and railroad
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 I-72 (eb) over FA320 (IL-121) & Cn RR built?

It was built in 1976, making it 49 years old in 2025.

What condition is I-72 (eb) over FA320 (IL-121) & Cn RR 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 December 2024.

How much traffic does I-72 (eb) over FA320 (IL-121) & Cn RR carry?

About 6,400 vehicles per day (2023 count), of which roughly 29% are trucks.

How long is I-72 (eb) over FA320 (IL-121) & Cn RR?

The structure is 267 ft (81.5 m) long with a longest span of 124 ft (37.9 m) and a deck 62 ft wide.

Who owns I-72 (eb) over FA320 (IL-121) & Cn RR?

It is owned by the State Highway Agency.