US Bridges

Interstate 81 Nbl over Interstate 77

Fair

Wythe County, Virginia · 2.02M to 52 & 1.12M to 11 · Structure no. 000000000022368

Built
1964
61 years old, rebuilt 1986
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
284 ft
4 main spans
Daily traffic
16,485
2022 count
Owner
State
State Highway Agency

About this bridge

Interstate 81 Nbl over Interstate 77 is a steel stringer/multi-beam or girder carrying Interstate 81 Nbl over Interstate 77 in Wythe County, Virginia. It was built in 1964 and reconstructed in 1986, so it is 61 years old, older than the Virginia average of 50.7 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 16,485 vehicles a day, roughly 1% of them trucks, projected to reach 20,809 by 2042. The structure is 284 ft (86.6 m) long and 35 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesInterstate 81 Nbl
CrossesInterstate 77
Location2.02M to 52 & 1.12M to 11
RouteInterstate 81
Coordinates36.96087, -81.06527
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
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 inspectionDecember 2023
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 geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating75 US tons
Inventory rating58 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length284 ft (86.6 m)
Longest span81 ft (24.7 m)
Deck width35 ft (10.7 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,485 (2022)
Projected traffic20,809 by 2042
Trucks1%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$131.3 million (2018 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was Interstate 81 Nbl over Interstate 77 built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 1986.

What condition is Interstate 81 Nbl over Interstate 77 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 December 2023.

How much traffic does Interstate 81 Nbl over Interstate 77 carry?

About 16,485 vehicles per day (2022 count), of which roughly 1% are trucks.

How long is Interstate 81 Nbl over Interstate 77?

The structure is 284 ft (86.6 m) long with a longest span of 81 ft (24.7 m) and a deck 35 ft wide.

Who owns Interstate 81 Nbl over Interstate 77?

It is owned by the State Highway Agency.