US Bridges

I81 over South Fork Holston River

Good

Sullivan County, Tennessee · 1 M NE JCT I81&SR36 · Structure no. 82I00810017

Built
1973
52 years old
Condition
Good
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
1,094 ft
4 main spans
Daily traffic
32,258
2021 count
Owner
State
State Highway Agency

About this bridge

I81 over South Fork Holston River is a steel continuous stringer/multi-beam or girder carrying I81 over South Fork Holston River in Sullivan County, Tennessee. It was built in 1973, so it is 52 years old, older than the Tennessee average of 47.4 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 32,258 vehicles a day, roughly 6% of them trucks, projected to reach 51,613 by 2042. The structure is 1,094 ft (333.5 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI81
CrossesSouth Fork Holston River
Location1 M NE JCT I81&SR36
RouteInterstate 81
Coordinates36.48167, -82.47833
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating37.8 US tons
Inventory rating29.7 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length1,094 ft (333.5 m)
Longest span315 ft (96 m)
Deck width44 ft (13.4 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic32,258 (2021)
Projected traffic51,613 by 2042
Trucks6%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 I81 over South Fork Holston River built?

It was built in 1973, making it 52 years old in 2025.

What condition is I81 over South Fork Holston River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2024.

How much traffic does I81 over South Fork Holston River carry?

About 32,258 vehicles per day (2021 count), of which roughly 6% are trucks.

How long is I81 over South Fork Holston River?

The structure is 1,094 ft (333.5 m) long with a longest span of 315 ft (96 m) and a deck 44 ft wide.

Who owns I81 over South Fork Holston River?

It is owned by the State Highway Agency.