US Bridges

Flat Run over Flat Run

Fair

Knox County, Ohio · 0.1 MI West of Edgar Road · Structure no. 4234634

Built
1900
125 years old, rebuilt 1978
Condition
Fair
inspected April 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
34 ft
1 main span
Daily traffic
426
2015 count
Owner
County
County Highway Agency

About this bridge

Flat Run over Flat Run is a prestressed concrete box beam or girders - multiple carrying Flat Run over Flat Run in Knox County, Ohio. It was built in 1900 and reconstructed in 1978, so it is 125 years old, older than the Ohio average of 47.3 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 426 vehicles a day, roughly 8% of them trucks, projected to reach 591 by 2042. The structure is 34 ft (10.4 m) long and 24 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesFlat Run
CrossesFlat Run
Location0.1 MI West of Edgar Road
RouteCounty Highway 40
CountyKnox County
StateOhio
Coordinates40.41255, -82.21712
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 inspectionApril 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating57.1 US tons
Inventory rating39.2 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length34 ft (10.4 m)
Longest span32 ft (9.8 m)
Deck width24 ft (7.4 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic426 (2015)
Projected traffic591 by 2042
Trucks8%
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

OwnerCounty Highway Agency
Maintained byCounty 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 Flat Run over Flat Run built?

It was built in 1900, making it 125 years old in 2025. It was reconstructed in 1978.

What condition is Flat Run over Flat Run 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 2024.

How much traffic does Flat Run over Flat Run carry?

About 426 vehicles per day (2015 count), of which roughly 8% are trucks.

How long is Flat Run over Flat Run?

The structure is 34 ft (10.4 m) long with a longest span of 32 ft (9.8 m) and a deck 24 ft wide.

Who owns Flat Run over Flat Run?

It is owned by the County Highway Agency.