US Bridges

I 39&US 51 over Harmon Creek South

Fair

Lee County, Illinois · 3 MI N of US 30 · Structure no. 052200400000000

Built
1982
43 years old
Condition
Fair
inspected July 2023
Type
Culvert
Concrete
Length
22 ft
2 main spans
Daily traffic
19,100
2023 count
Owner
State
State Highway Agency

About this bridge

I 39&US 51 over Harmon Creek South is a concrete culvert carrying I 39&US 51 over Harmon Creek South in Lee County, Illinois. It was built in 1982, so it is 43 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 19,100 vehicles a day, roughly 41% of them trucks, projected to reach 19,594 by 2046. The structure is 22 ft (6.6 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 39&US 51
CrossesHarmon Creek South
Location3 MI N of US 30
RouteInterstate 39
CountyLee County
StateIllinois
Coordinates41.80263, -89.0093
Functional classRural 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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating107.1 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadHS 20 + Mod
Structure length22 ft (6.6 m)
Longest span10 ft (3.2 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic19,100 (2023)
Projected traffic19,594 by 2046
Trucks41%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was I 39&US 51 over Harmon Creek South built?

It was built in 1982, making it 43 years old in 2025.

What condition is I 39&US 51 over Harmon Creek South 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 July 2023.

How much traffic does I 39&US 51 over Harmon Creek South carry?

About 19,100 vehicles per day (2023 count), of which roughly 41% are trucks.

How long is I 39&US 51 over Harmon Creek South?

The structure is 22 ft (6.6 m) long with a longest span of 10 ft (3.2 m).

Who owns I 39&US 51 over Harmon Creek South?

It is owned by the State Highway Agency.