US Bridges

I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo

Fair

St. Clair County, Illinois · Pier D1 to Abut D46 · Structure no. 082014400000000

Built
1969
56 years old, rebuilt 2021
Condition
Fair
inspected February 2024
Type
Girder and Floorbeam System
Steel Continuous
Length
4,444 ft
46 main spans
Daily traffic
24,300
2024 count
Owner
State
State Highway Agency

About this bridge

I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo is a steel continuous girder and floorbeam system carrying I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo in St. Clair County, Illinois. It was built in 1969 and reconstructed in 2021, so it is 56 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 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 24,300 vehicles a day, roughly 7% of them trucks, projected to reach 22,826 by 2046. The structure is 4,444 ft (1,354.5 m) long and 36 ft wide. If it were closed, the detour would be 29.8 mi (48 km).

Location

Open in Google Maps
CarriesI-55/64 EB Cd "d"
CrossesUPRR O2 8TH9TH10th Piggo
LocationPier D1 to Abut D46
CountySt. Clair County
StateIllinois
Coordinates38.6168, -90.17846
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
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 2024
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 geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.3 US tons
Inventory rating26.5 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans46
Design loadHS 20 + Mod
Structure length4,444 ft (1,354.5 m)
Longest span137 ft (41.8 m)
Deck width36 ft (11 m)
Roadway width31 ft (9.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic24,300 (2024)
Projected traffic22,826 by 2046
Trucks7%
Lanes on structure2
Traffic directionOne-way traffic
CarriesThird level (interchange)
CrossesHighway and railroad
Detour if closed29.8 mi (48 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$258.9 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo built?

It was built in 1969, making it 56 years old in 2025. It was reconstructed in 2021.

What condition is I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo 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 February 2024.

How much traffic does I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo carry?

About 24,300 vehicles per day (2024 count), of which roughly 7% are trucks.

How long is I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo?

The structure is 4,444 ft (1,354.5 m) long with a longest span of 137 ft (41.8 m) and a deck 36 ft wide.

Who owns I-55/64 EB Cd "d" over UPRR O2 8TH9TH10th Piggo?

It is owned by the State Highway Agency.