US Bridges

TR-170 over North Fork

Fair

Marion County, Illinois · 3.5 MI Ese Vernon · Structure no. 061309600000000

Built
1921
104 years old
Condition
Fair
inspected April 2023
Type
Slab
Concrete
Length
33 ft
1 main span
Daily traffic
25
2022 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR-170 over North Fork is a concrete slab carrying TR-170 over North Fork in Marion County, Illinois. It was built in 1921, so it is 104 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 25 vehicles a day, roughly 20% of them trucks, projected to reach 25 by 2046. The structure is 33 ft (10.1 m) long and 17 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesTR-170
CrossesNorth Fork
Location3.5 MI Ese Vernon
RouteCounty Highway 0
CountyMarion County
StateIllinois
Coordinates38.78889, -89.01435
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating44.6 US tons
Inventory rating26.8 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length33 ft (10.1 m)
Longest span31 ft (9.4 m)
Deck width17 ft (5.2 m)
Roadway width15 ft (4.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25 (2022)
Projected traffic25 by 2046
Trucks20%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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-170 over North Fork built?

It was built in 1921, making it 104 years old in 2025.

What condition is TR-170 over North Fork 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 2023.

How much traffic does TR-170 over North Fork carry?

About 25 vehicles per day (2022 count), of which roughly 20% are trucks.

How long is TR-170 over North Fork?

The structure is 33 ft (10.1 m) long with a longest span of 31 ft (9.4 m) and a deck 17 ft wide.

Who owns TR-170 over North Fork?

It is owned by the Town or Township Highway Agency.