US Bridges

I-74 EB over Flatrock River

Fair

Decatur County, Indiana · 05.05 W US 421 · Structure no. 045020

Built
1961
64 years old, rebuilt 2016
Condition
Fair
inspected March 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
307 ft
5 main spans
Daily traffic
11,343
2015 count
Owner
State
State Highway Agency

About this bridge

I-74 EB over Flatrock River is a steel continuous stringer/multi-beam or girder carrying I-74 EB over Flatrock River in Decatur County, Indiana. It was built in 1961 and reconstructed in 2016, so it is 64 years old, older than the Indiana average of 46.6 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 11,343 vehicles a day, roughly 28% of them trucks, projected to reach 15,507 by 2036. The structure is 307 ft (93.5 m) long and 41 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesI-74 EB
CrossesFlatrock River
Location05.05 W US 421
RouteInterstate 74
CountyDecatur County
StateIndiana
Coordinates39.41906, -85.57492
Functional classRural Principal Arterial - Interstate

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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2024
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 geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating33.2 US tons
Inventory rating25.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20 + Mod
Structure length307 ft (93.5 m)
Longest span68 ft (20.7 m)
Deck width41 ft (12.5 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic11,343 (2015)
Projected traffic15,507 by 2036
Trucks28%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 I-74 EB over Flatrock River built?

It was built in 1961, making it 64 years old in 2025. It was reconstructed in 2016.

What condition is I-74 EB over Flatrock River 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 March 2024.

How much traffic does I-74 EB over Flatrock River carry?

About 11,343 vehicles per day (2015 count), of which roughly 28% are trucks.

How long is I-74 EB over Flatrock River?

The structure is 307 ft (93.5 m) long with a longest span of 68 ft (20.7 m) and a deck 41 ft wide.

Who owns I-74 EB over Flatrock River?

It is owned by the State Highway Agency.