US Bridges

Ill 97 over Rock Creek

Good

Menard County, Illinois · 3.5M N Salisbury · Structure no. 065001700000000

Built
1989
36 years old
Condition
Good
inspected February 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
97 ft
1 main span
Daily traffic
3,900
2023 count
Owner
State
State Highway Agency

About this bridge

Ill 97 over Rock Creek is a prestressed concrete stringer/multi-beam or girder carrying Ill 97 over Rock Creek in Menard County, Illinois. It was built in 1989, so it is 36 years old, younger than the Illinois average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 3,900 vehicles a day, roughly 6% of them trucks, projected to reach 3,788 by 2046. The structure is 97 ft (29.5 m) long and 35 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

CarriesIll 97
CrossesRock Creek
Location3.5M N Salisbury
RouteState Highway 97
Coordinates39.9191, -89.8403
Functional classRural Minor Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating98.2 US tons
Inventory rating44.6 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length97 ft (29.5 m)
Longest span94 ft (28.7 m)
Deck width35 ft (10.7 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,900 (2023)
Projected traffic3,788 by 2046
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ill 97 over Rock Creek built?

It was built in 1989, making it 36 years old in 2025.

What condition is Ill 97 over Rock Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in February 2023.

How much traffic does Ill 97 over Rock Creek carry?

About 3,900 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is Ill 97 over Rock Creek?

The structure is 97 ft (29.5 m) long with a longest span of 94 ft (28.7 m) and a deck 35 ft wide.

Who owns Ill 97 over Rock Creek?

It is owned by the State Highway Agency.