US Bridges

Il 71 (fap 311) over Trib to Fox River

Good

LaSalle County, Illinois · 1.4 MI SW of US 52 · Structure no. 050265100000000

Built
2014
11 years old
Condition
Good
inspected January 2021
Type
Culvert
Concrete
Length
23 ft
2 main spans
Daily traffic
4,600
2023 count
Owner
State
State Highway Agency

About this bridge

Il 71 (fap 311) over Trib to Fox River is a concrete culvert carrying Il 71 (fap 311) over Trib to Fox River in LaSalle County, Illinois. It was built in 2014, so it is 11 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 4,600 vehicles a day, roughly 12% of them trucks, projected to reach 3,990 by 2046. The structure is 23 ft (7 m) long and 81 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesIl 71 (fap 311)
CrossesTrib to Fox River
Location1.4 MI SW of US 52
RouteState Highway 71
CountyLaSalle County
StateIllinois
Coordinates41.46914, -88.66274
Functional classRural Principal Arterial - Other

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionJanuary 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating83.6 US tons
Inventory rating64.6 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 25 or greater
Structure length23 ft (7 m)
Longest span11 ft (3.4 m)
Deck width81 ft (24.6 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,600 (2023)
Projected traffic3,990 by 2046
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Il 71 (fap 311) over Trib to Fox River built?

It was built in 2014, making it 11 years old in 2025.

What condition is Il 71 (fap 311) over Trib to Fox River 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 January 2021.

How much traffic does Il 71 (fap 311) over Trib to Fox River carry?

About 4,600 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is Il 71 (fap 311) over Trib to Fox River?

The structure is 23 ft (7 m) long with a longest span of 11 ft (3.4 m) and a deck 81 ft wide.

Who owns Il 71 (fap 311) over Trib to Fox River?

It is owned by the State Highway Agency.