US Bridges

TR 305 over Slough Creek

Fair

Perry County, Illinois · 1 MI West of Ch 18 · Structure no. 073310300000000

Built
1978
47 years old
Condition
Fair
inspected January 2025
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
58 ft
1 main span
Daily traffic
50
2024 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR 305 over Slough Creek is a prestressed concrete box beam or girders - multiple carrying TR 305 over Slough Creek in Perry 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 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 50 vehicles a day, roughly 40% of them trucks, projected to reach 76 by 2046. The structure is 58 ft (17.7 m) long and 21 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesTR 305
CrossesSlough Creek
Location1 MI West of Ch 18
RouteCounty Highway 0
CountyPerry County
StateIllinois
Coordinates37.96697, -89.38251
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.9 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length58 ft (17.7 m)
Longest span55 ft (16.8 m)
Deck width21 ft (6.4 m)
Roadway width21 ft (6.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2024)
Projected traffic76 by 2046
Trucks40%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 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 305 over Slough Creek built?

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

What condition is TR 305 over Slough 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 January 2025.

How much traffic does TR 305 over Slough Creek carry?

About 50 vehicles per day (2024 count), of which roughly 40% are trucks.

How long is TR 305 over Slough Creek?

The structure is 58 ft (17.7 m) long with a longest span of 55 ft (16.8 m) and a deck 21 ft wide.

Who owns TR 305 over Slough Creek?

It is owned by the Town or Township Highway Agency.