US Bridges

Ill 73 over Straddle Creek

Fair

Carroll County, Illinois · 0.2 MI N of Lanark · Structure no. 008003600000000

Built
1989
36 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
105 ft
1 main span
Daily traffic
3,350
2023 count
Owner
State
State Highway Agency

About this bridge

Ill 73 over Straddle Creek is a prestressed concrete stringer/multi-beam or girder carrying Ill 73 over Straddle Creek in Carroll County, Illinois. It was built in 1989, so it is 36 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 3,350 vehicles a day, roughly 12% of them trucks, projected to reach 3,485 by 2046. The structure is 105 ft (31.9 m) long and 35 ft wide. If it were closed, the detour would be 34.8 mi (56 km).

Location

Open in Google Maps
CarriesIll 73
CrossesStraddle Creek
Location0.2 MI N of Lanark
RouteState Highway 73
CountyCarroll County
StateIllinois
Coordinates42.11273, -89.83234
Functional classRural 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.
Superstructure8 Very GoodNo problems noted.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum 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 rating98.2 US tons
Inventory rating41.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length105 ft (31.9 m)
Longest span102 ft (31.1 m)
Deck width35 ft (10.7 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,350 (2023)
Projected traffic3,485 by 2046
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed34.8 mi (56 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 Ill 73 over Straddle Creek built?

It was built in 1989, making it 36 years old in 2025.

What condition is Ill 73 over Straddle 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 June 2023.

How much traffic does Ill 73 over Straddle Creek carry?

About 3,350 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is Ill 73 over Straddle Creek?

The structure is 105 ft (31.9 m) long with a longest span of 102 ft (31.1 m) and a deck 35 ft wide.

Who owns Ill 73 over Straddle Creek?

It is owned by the State Highway Agency.