US Bridges

Knox ST over I-74

Fair

Knox County, Illinois · S of Galesburg Inter · Structure no. 048005800000000

Built
1964
61 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
257 ft
4 main spans
Daily traffic
550
2022 count
Owner
State
State Highway Agency

About this bridge

Knox ST over I-74 is a steel continuous stringer/multi-beam or girder carrying Knox ST over I-74 in Knox County, Illinois. It was built in 1964, 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 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 550 vehicles a day, roughly 16% of them trucks, projected to reach 657 by 2046. The structure is 257 ft (78.3 m) long and 31 ft wide.

Location

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CarriesKnox ST
CrossesI-74
LocationS of Galesburg Inter
CountyKnox County
StateIllinois
Coordinates40.94006, -90.33211
Functional classRural Minor 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 inspectionDecember 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.8 US tons
Inventory rating42.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length257 ft (78.3 m)
Longest span84 ft (25.5 m)
Deck width31 ft (9.5 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic550 (2022)
Projected traffic657 by 2046
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
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 Knox ST over I-74 built?

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

What condition is Knox ST over I-74 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 2023.

How much traffic does Knox ST over I-74 carry?

About 550 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is Knox ST over I-74?

The structure is 257 ft (78.3 m) long with a longest span of 84 ft (25.5 m) and a deck 31 ft wide.

Who owns Knox ST over I-74?

It is owned by the State Highway Agency.