US Bridges

I26 Rt LN over SR 400 WB (unaka St)

Fair

Washington County, Tennessee · In Johnson City · Structure no. 90I00260043

Built
1975
50 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
134 ft
3 main spans
Daily traffic
55,938
2021 count
Owner
State
State Highway Agency

About this bridge

I26 Rt LN over SR 400 WB (unaka St) is a prestressed concrete stringer/multi-beam or girder carrying I26 Rt LN over SR 400 WB (unaka St) in Washington County, Tennessee. It was built in 1975, so it is 50 years old, older than the Tennessee average of 47.4 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 55,938 vehicles a day, roughly 6% of them trucks, projected to reach 70,435 by 2042. The structure is 134 ft (40.7 m) long and 44 ft wide.

Location

Open in Google Maps
CarriesI26 Rt LN
CrossesSR 400 WB (unaka St)
LocationIn Johnson City
RouteInterstate 26
CountyWashington County
StateTennessee
Coordinates36.3255, -82.35419
Functional classUrban 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating76.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length134 ft (40.7 m)
Longest span63 ft (19.2 m)
Deck width44 ft (13.4 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic55,938 (2021)
Projected traffic70,435 by 2042
Trucks6%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I26 Rt LN over SR 400 WB (unaka St) built?

It was built in 1975, making it 50 years old in 2025.

What condition is I26 Rt LN over SR 400 WB (unaka St) 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 September 2023.

How much traffic does I26 Rt LN over SR 400 WB (unaka St) carry?

About 55,938 vehicles per day (2021 count), of which roughly 6% are trucks.

How long is I26 Rt LN over SR 400 WB (unaka St)?

The structure is 134 ft (40.7 m) long with a longest span of 63 ft (19.2 m) and a deck 44 ft wide.

Who owns I26 Rt LN over SR 400 WB (unaka St)?

It is owned by the State Highway Agency.