US Bridges

Harmon RD over I-88

Fair

Lee County, Illinois · 4 MI N of Harmon · Structure no. 052991300000000

Built
1974
51 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
221 ft
4 main spans
Daily traffic
325
2022 count
Owner
Toll Authority
State Toll Authority

About this bridge

Harmon RD over I-88 is a prestressed concrete stringer/multi-beam or girder carrying Harmon RD over I-88 in Lee County, Illinois. It was built in 1974, so it is 51 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 325 vehicles a day, roughly 7% of them trucks, projected to reach 404 by 2046. The structure is 221 ft (67.4 m) long and 34 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesHarmon RD
CrossesI-88
Location4 MI N of Harmon
RouteCounty Highway 0
CountyLee County
StateIllinois
Coordinates41.78, -89.55359
Functional classRural Major 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
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 inspectionJune 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 geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating74 US tons
Inventory rating44.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans4
Design loadHS 20
Structure length221 ft (67.4 m)
Longest span79 ft (24.1 m)
Deck width34 ft (10.3 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic325 (2022)
Projected traffic404 by 2046
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Toll Authority
Maintained byState Toll Authority
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 Harmon RD over I-88 built?

It was built in 1974, making it 51 years old in 2025.

What condition is Harmon RD over I-88 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 June 2023.

How much traffic does Harmon RD over I-88 carry?

About 325 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is Harmon RD over I-88?

The structure is 221 ft (67.4 m) long with a longest span of 79 ft (24.1 m) and a deck 34 ft wide.

Who owns Harmon RD over I-88?

It is owned by the State Toll Authority.