US Bridges

Il 176 over Des Plaines River

Fair

Lake County, Illinois · 0.9 M E of Il 21 · Structure no. 049006800000000

Built
1925
100 years old, rebuilt 1983
Condition
Fair
inspected February 2025
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
144 ft
3 main spans
Daily traffic
14,300
2023 count
Owner
State
State Highway Agency

About this bridge

Il 176 over Des Plaines River is a steel continuous stringer/multi-beam or girder carrying Il 176 over Des Plaines River in Lake County, Illinois. It was built in 1925 and reconstructed in 1983, so it is 100 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 14,300 vehicles a day, roughly 2% of them trucks, projected to reach 12,928 by 2046. The structure is 144 ft (43.9 m) long and 54 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesIl 176
CrossesDes Plaines River
Location0.9 M E of Il 21
RouteState Highway 176
CountyLake County
StateIllinois
Coordinates42.28107, -87.93403
Functional classUrban Minor Arterial

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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating78.6 US tons
Inventory rating44.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length144 ft (43.9 m)
Longest span48 ft (14.6 m)
Deck width54 ft (16.5 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic14,300 (2023)
Projected traffic12,928 by 2046
Trucks2%
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.4 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Il 176 over Des Plaines River built?

It was built in 1925, making it 100 years old in 2025. It was reconstructed in 1983.

What condition is Il 176 over Des Plaines River 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 February 2025.

How much traffic does Il 176 over Des Plaines River carry?

About 14,300 vehicles per day (2023 count), of which roughly 2% are trucks.

How long is Il 176 over Des Plaines River?

The structure is 144 ft (43.9 m) long with a longest span of 48 ft (14.6 m) and a deck 54 ft wide.

Who owns Il 176 over Des Plaines River?

It is owned by the State Highway Agency.