US Bridges

I-88 EB over Rock Creek

Fair

Whiteside County, Illinois · 4.5 Mi. Ne. Erie · Structure no. 098005900000000

Built
1975
50 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
177 ft
3 main spans
Daily traffic
6,550
2023 count
Owner
State
State Highway Agency

About this bridge

I-88 EB over Rock Creek is a steel continuous stringer/multi-beam or girder carrying I-88 EB over Rock Creek in Whiteside County, Illinois. It was built in 1975, so it is 50 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 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 6,550 vehicles a day, roughly 34% of them trucks, projected to reach 7,272 by 2046. The structure is 177 ft (53.8 m) long and 42 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-88 EB
CrossesRock Creek
Location4.5 Mi. Ne. Erie
RouteInterstate 88
CountyWhiteside County
StateIllinois
Coordinates41.70816, -90.02532
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure8 Very GoodNo problems noted.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 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 geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
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 spans3
Design loadHS 20
Structure length177 ft (53.8 m)
Longest span75 ft (22.9 m)
Deck width42 ft (12.8 m)
Roadway width38 ft (11.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,550 (2023)
Projected traffic7,272 by 2046
Trucks34%
Lanes on structure2
Traffic directionOne-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-88 EB over Rock Creek built?

It was built in 1975, making it 50 years old in 2025.

What condition is I-88 EB over Rock Creek 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 September 2023.

How much traffic does I-88 EB over Rock Creek carry?

About 6,550 vehicles per day (2023 count), of which roughly 34% are trucks.

How long is I-88 EB over Rock Creek?

The structure is 177 ft (53.8 m) long with a longest span of 75 ft (22.9 m) and a deck 42 ft wide.

Who owns I-88 EB over Rock Creek?

It is owned by the State Highway Agency.