US Bridges

TR 108 over Rock CR

Good

Menard County, Illinois · 3.0 MI SW Athens · Structure no. 065308700000000

Built
2021
4 years old
Condition
Good
inspected October 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
75 ft
1 main span
Daily traffic
125
2020 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR 108 over Rock CR is a prestressed concrete box beam or girders - multiple carrying TR 108 over Rock CR in Menard County, Illinois. It was built in 2021, so it is 4 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 125 vehicles a day, roughly 3% of them trucks, projected to reach 126 by 2046. The structure is 75 ft (22.8 m) long and 28 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesTR 108
CrossesRock CR
Location3.0 MI SW Athens
RouteCounty Highway 0
CountyMenard County
StateIllinois
Coordinates39.94224, -89.78389
Functional classRural Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating78.3 US tons
Inventory rating60.4 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 25 or greater
Structure length75 ft (22.8 m)
Longest span72 ft (21.9 m)
Deck width28 ft (8.5 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic125 (2020)
Projected traffic126 by 2046
Trucks3%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerTown or Township Highway Agency
Maintained byTown or Township 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 TR 108 over Rock CR built?

It was built in 2021, making it 4 years old in 2025.

What condition is TR 108 over Rock CR 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 October 2023.

How much traffic does TR 108 over Rock CR carry?

About 125 vehicles per day (2020 count), of which roughly 3% are trucks.

How long is TR 108 over Rock CR?

The structure is 75 ft (22.8 m) long with a longest span of 72 ft (21.9 m) and a deck 28 ft wide.

Who owns TR 108 over Rock CR?

It is owned by the Town or Township Highway Agency.