US Bridges

Il 178 over I & M Canal

Good

LaSalle County, Illinois · 1.47 M S of US 6 · Structure no. 050025000000000

Built
2012
13 years old
Condition
Good
inspected February 2022
Type
Stringer/Multi-beam or Girder
Steel
Length
45 ft
1 main span
Daily traffic
3,600
2023 count
Owner
State
State Highway Agency

About this bridge

Il 178 over I & M Canal is a steel stringer/multi-beam or girder carrying Il 178 over I & M Canal in LaSalle County, Illinois. It was built in 2012, so it is 13 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 3,600 vehicles a day, roughly 17% of them trucks, projected to reach 3,182 by 2046. The structure is 45 ft (13.7 m) long and 44 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesIl 178
CrossesI & M Canal
Location1.47 M S of US 6
RouteState Highway 178
CountyLaSalle County
StateIllinois
Coordinates41.3403, -89.01058
Functional classUrban Collector

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 protection7 GoodSome minor problems.
Last inspectionFebruary 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating76.8 US tons
Inventory rating46.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length45 ft (13.7 m)
Longest span44 ft (13.4 m)
Deck width44 ft (13.5 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,600 (2023)
Projected traffic3,182 by 2046
Trucks17%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 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 Il 178 over I & M Canal built?

It was built in 2012, making it 13 years old in 2025.

What condition is Il 178 over I & M Canal 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 2022.

How much traffic does Il 178 over I & M Canal carry?

About 3,600 vehicles per day (2023 count), of which roughly 17% are trucks.

How long is Il 178 over I & M Canal?

The structure is 45 ft (13.7 m) long with a longest span of 44 ft (13.4 m) and a deck 44 ft wide.

Who owns Il 178 over I & M Canal?

It is owned by the State Highway Agency.