US Bridges

Prophetstown RD over I-88

Fair

Whiteside County, Illinois · 2.5 MI W Rock Falls · Structure no. 098008100000000

Built
1972
53 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
267 ft
2 main spans
Daily traffic
2,100
2021 count
Owner
State
State Highway Agency

About this bridge

Prophetstown RD over I-88 is a steel continuous stringer/multi-beam or girder carrying Prophetstown RD over I-88 in Whiteside County, Illinois. It was built in 1972, so it is 53 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 2,100 vehicles a day, roughly 6% of them trucks, projected to reach 2,121 by 2046. The structure is 267 ft (81.5 m) long and 46 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesProphetstown RD
CrossesI-88
Location2.5 MI W Rock Falls
RouteCounty Highway 0
CountyWhiteside County
StateIllinois
Coordinates41.75214, -89.75888
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating76.4 US tons
Inventory rating45.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20 + Mod
Structure length267 ft (81.5 m)
Longest span109 ft (33.1 m)
Deck width46 ft (14 m)
Roadway width43 ft (13 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,100 (2021)
Projected traffic2,121 by 2046
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.7 mi (6 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 Prophetstown RD over I-88 built?

It was built in 1972, making it 53 years old in 2025.

What condition is Prophetstown 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 December 2023.

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

About 2,100 vehicles per day (2021 count), of which roughly 6% are trucks.

How long is Prophetstown RD over I-88?

The structure is 267 ft (81.5 m) long with a longest span of 109 ft (33.1 m) and a deck 46 ft wide.

Who owns Prophetstown RD over I-88?

It is owned by the State Highway Agency.