US Bridges

TR 339 over Mount Branch

Fair

Clark County, Illinois · 2.0 MI NW Moriah · Structure no. 012321000000000

Built
1979
46 years old
Condition
Fair
inspected February 2025
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
40 ft
1 main span
Daily traffic
200
2021 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR 339 over Mount Branch is a prestressed concrete box beam or girders - multiple carrying TR 339 over Mount Branch in Clark County, Illinois. It was built in 1979, so it is 46 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 200 vehicles a day, roughly 1% of them trucks, projected to reach 202 by 2046. The structure is 40 ft (12.2 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesTR 339
CrossesMount Branch
Location2.0 MI NW Moriah
RouteCounty Highway 0
CountyClark County
StateIllinois
Coordinates39.23299, -87.97484
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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionFebruary 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 adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum 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 length40 ft (12.2 m)
Longest span39 ft (11.9 m)
Deck width26 ft (8 m)
Roadway width26 ft (8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic200 (2021)
Projected traffic202 by 2046
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 339 over Mount Branch built?

It was built in 1979, making it 46 years old in 2025.

What condition is TR 339 over Mount Branch 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 339 over Mount Branch carry?

About 200 vehicles per day (2021 count), of which roughly 1% are trucks.

How long is TR 339 over Mount Branch?

The structure is 40 ft (12.2 m) long with a longest span of 39 ft (11.9 m) and a deck 26 ft wide.

Who owns TR 339 over Mount Branch?

It is owned by the Town or Township Highway Agency.