US Bridges

Il 173 over Beaver Creek

Fair

Boone County, Illinois · 2.0 MI E Poplar Grov · Structure no. 004002000000000

Built
2008
17 years old
Condition
Fair
inspected April 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
130 ft
2 main spans
Daily traffic
4,550
2023 count
Owner
State
State Highway Agency

About this bridge

Il 173 over Beaver Creek is a prestressed concrete continuous stringer/multi-beam or girder carrying Il 173 over Beaver Creek in Boone County, Illinois. It was built in 2008, so it is 17 years old, younger 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 4,550 vehicles a day, roughly 10% of them trucks, projected to reach 5,044 by 2046. The structure is 130 ft (39.7 m) long and 43 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesIl 173
CrossesBeaver Creek
Location2.0 MI E Poplar Grov
RouteState Highway 173
CountyBoone County
StateIllinois
Coordinates42.37559, -88.7794
Functional classRural Principal Arterial - Other

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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2024
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating67.5 US tons
Inventory rating40.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length130 ft (39.7 m)
Longest span65 ft (19.8 m)
Deck width43 ft (13.2 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,550 (2023)
Projected traffic5,044 by 2046
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 173 over Beaver Creek built?

It was built in 2008, making it 17 years old in 2025.

What condition is Il 173 over Beaver Creek 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 April 2024.

How much traffic does Il 173 over Beaver Creek carry?

About 4,550 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Il 173 over Beaver Creek?

The structure is 130 ft (39.7 m) long with a longest span of 65 ft (19.8 m) and a deck 43 ft wide.

Who owns Il 173 over Beaver Creek?

It is owned by the State Highway Agency.