US Bridges

TR 171 over Prairie Ck

Fair

Mason County, Illinois · 4.5 MI Esemason Cty · Structure no. 063431300000000

Built
1978
47 years old
Condition
Fair
inspected February 2025
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
129 ft
3 main spans
Daily traffic
175
2024 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR 171 over Prairie Ck is a prestressed concrete box beam or girders - multiple carrying TR 171 over Prairie Ck in Mason County, Illinois. It was built in 1978, so it is 47 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 5 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 175 vehicles a day, roughly 4% of them trucks, projected to reach 177 by 2046. The structure is 129 ft (39.3 m) long and 24 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesTR 171
CrossesPrairie Ck
Location4.5 MI Esemason Cty
RouteCounty Highway 0
Coordinates40.17924, -89.60742
Functional classRural Local

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.6 US tons
Inventory rating35.7 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length129 ft (39.3 m)
Longest span42 ft (12.8 m)
Deck width24 ft (7.4 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic175 (2024)
Projected traffic177 by 2046
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerTown or Township Highway Agency
Maintained byTown or Township 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 TR 171 over Prairie Ck built?

It was built in 1978, making it 47 years old in 2025.

What condition is TR 171 over Prairie Ck 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 TR 171 over Prairie Ck carry?

About 175 vehicles per day (2024 count), of which roughly 4% are trucks.

How long is TR 171 over Prairie Ck?

The structure is 129 ft (39.3 m) long with a longest span of 42 ft (12.8 m) and a deck 24 ft wide.

Who owns TR 171 over Prairie Ck?

It is owned by the Town or Township Highway Agency.