US Bridges

I-81 Sbl over Island RD & Mumpower Ck

Fair

Washington County, Virginia · 1.96 R 11 &3.58 Tenn Line · Structure no. 000000000020022

Built
1961
64 years old, rebuilt 2001
Condition
Fair
inspected June 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
252 ft
5 main spans
Daily traffic
22,477
2022 count
Owner
State
State Highway Agency

About this bridge

I-81 Sbl over Island RD & Mumpower Ck is a prestressed concrete box beam or girders - multiple carrying I-81 Sbl over Island RD & Mumpower Ck in Washington County, Virginia. It was built in 1961 and reconstructed in 2001, so it is 64 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 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 22,477 vehicles a day, roughly 1% of them trucks, projected to reach 26,325 by 2042. The structure is 252 ft (76.8 m) long and 62 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesI-81 Sbl
CrossesIsland RD & Mumpower Ck
Location1.96 R 11 &3.58 Tenn Line
RouteInterstate 81
Coordinates36.62141, -82.18937
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating64 US tons
Inventory rating49.1 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20 + Mod
Structure length252 ft (76.8 m)
Longest span56 ft (17.1 m)
Deck width62 ft (18.8 m)
Roadway width59 ft (17.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic22,477 (2022)
Projected traffic26,325 by 2042
Trucks1%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and waterway
Detour if closed6.2 mi (10 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$97.5 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-81 Sbl over Island RD & Mumpower Ck built?

It was built in 1961, making it 64 years old in 2025. It was reconstructed in 2001.

What condition is I-81 Sbl over Island RD & Mumpower Ck 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 June 2024.

How much traffic does I-81 Sbl over Island RD & Mumpower Ck carry?

About 22,477 vehicles per day (2022 count), of which roughly 1% are trucks.

How long is I-81 Sbl over Island RD & Mumpower Ck?

The structure is 252 ft (76.8 m) long with a longest span of 56 ft (17.1 m) and a deck 62 ft wide.

Who owns I-81 Sbl over Island RD & Mumpower Ck?

It is owned by the State Highway Agency.