US Bridges

Ill 84 over Rock River

Fair

Henry County, Illinois · At Rock Island CO LN · Structure no. 037012800000000

Built
1981
44 years old
Condition
Fair
inspected July 2023
Type
Box Beam or Girders - Single or Spread
Steel Continuous
Length
984 ft
6 main spans
Daily traffic
12,400
2023 count
Owner
State
State Highway Agency

About this bridge

Ill 84 over Rock River is a steel continuous box beam or girders - single or spread carrying Ill 84 over Rock River in Henry County, Illinois. It was built in 1981, so it is 44 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 12,400 vehicles a day, roughly 3% of them trucks, projected to reach 12,960 by 2046. The structure is 984 ft (299.9 m) long and 93 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesIll 84
CrossesRock River
LocationAt Rock Island CO LN
RouteState Highway 84
CountyHenry County
StateIllinois
Coordinates41.48368, -90.37423
Functional classUrban Other Principal 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating52.5 US tons
Inventory rating31.4 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20 + Mod
Structure length984 ft (299.9 m)
Longest span176 ft (53.6 m)
Deck width93 ft (28.4 m)
Roadway width87 ft (26.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,400 (2023)
Projected traffic12,960 by 2046
Trucks3%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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 proposedNone recorded
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Ill 84 over Rock River built?

It was built in 1981, making it 44 years old in 2025.

What condition is Ill 84 over Rock River 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 Ill 84 over Rock River carry?

About 12,400 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Ill 84 over Rock River?

The structure is 984 ft (299.9 m) long with a longest span of 176 ft (53.6 m) and a deck 93 ft wide.

Who owns Ill 84 over Rock River?

It is owned by the State Highway Agency.