US Bridges

Ill 64 over I-39 & US 51

Fair

Ogle County, Illinois · 4 Mi. W of Dekalb CO · Structure no. 071005500000000

Built
1980
45 years old
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
266 ft
2 main spans
Daily traffic
4,300
2023 count
Owner
State
State Highway Agency

About this bridge

Ill 64 over I-39 & US 51 is a steel continuous stringer/multi-beam or girder carrying Ill 64 over I-39 & US 51 in Ogle County, Illinois. It was built in 1980, so it is 45 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 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 4,300 vehicles a day, roughly 14% of them trucks, projected to reach 4,472 by 2046. The structure is 266 ft (81.1 m) long and 68 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesIll 64
CrossesI-39 & US 51
Location4 Mi. W of Dekalb CO
RouteState Highway 64
CountyOgle County
StateIllinois
Coordinates42.00711, -89.02062
Functional classRural Minor Arterial

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating75 US tons
Inventory rating42.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20
Structure length266 ft (81.1 m)
Longest span113 ft (34.4 m)
Deck width68 ft (20.7 m)
Roadway width48 ft (14.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,300 (2023)
Projected traffic4,472 by 2046
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed9.9 mi (16 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 Ill 64 over I-39 & US 51 built?

It was built in 1980, making it 45 years old in 2025.

What condition is Ill 64 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 March 2023.

How much traffic does Ill 64 over I-39 & US 51 carry?

About 4,300 vehicles per day (2023 count), of which roughly 14% are trucks.

How long is Ill 64 over I-39 & US 51?

The structure is 266 ft (81.1 m) long with a longest span of 113 ft (34.4 m) and a deck 68 ft wide.

Who owns Ill 64 over I-39 & US 51?

It is owned by the State Highway Agency.