US Bridges

I26 over Tilson Mountain Rd.

Fair

Unicoi County, Tennessee · 5.62 MI from Nc/Tn ST LN · Structure no. 86I00260065

Built
1994
31 years old
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
295 ft
3 main spans
Daily traffic
8,759
2021 count
Owner
State
State Highway Agency

About this bridge

I26 over Tilson Mountain Rd. is a prestressed concrete continuous stringer/multi-beam or girder carrying I26 over Tilson Mountain Rd. in Unicoi County, Tennessee. It was built in 1994, so it is 31 years old, younger 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 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 8,759 vehicles a day, roughly 6% of them trucks, projected to reach 14,014 by 2042. The structure is 295 ft (89.9 m) long and 90 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesI26
CrossesTilson Mountain Rd.
Location5.62 MI from Nc/Tn ST LN
RouteInterstate 26
CountyUnicoi County
StateTennessee
Coordinates36.02726, -82.54223
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.6 US tons
Inventory rating26.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length295 ft (89.9 m)
Longest span99 ft (30.1 m)
Deck width90 ft (27.4 m)
Roadway width85 ft (25.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,759 (2021)
Projected traffic14,014 by 2042
Trucks6%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.1 mi (5 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I26 over Tilson Mountain Rd. built?

It was built in 1994, making it 31 years old in 2025.

What condition is I26 over Tilson Mountain Rd. 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 November 2024.

How much traffic does I26 over Tilson Mountain Rd. carry?

About 8,759 vehicles per day (2021 count), of which roughly 6% are trucks.

How long is I26 over Tilson Mountain Rd.?

The structure is 295 ft (89.9 m) long with a longest span of 99 ft (30.1 m) and a deck 90 ft wide.

Who owns I26 over Tilson Mountain Rd.?

It is owned by the State Highway Agency.