US Bridges

I77 Sbl over I85

Fair

Mecklenburg County, North Carolina · 0.9 Mi. N. Jct.Lasalle ST · Structure no. 000000001190303

Built
1970
55 years old, rebuilt 1989
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
257 ft
4 main spans
Daily traffic
73,500
2019 count
Owner
State
State Highway Agency

About this bridge

I77 Sbl over I85 is a steel stringer/multi-beam or girder carrying I77 Sbl over I85 in Mecklenburg County, North Carolina. It was built in 1970 and reconstructed in 1989, so it is 55 years old, older than the North Carolina average of 38.7 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 73,500 vehicles a day, roughly 16% of them trucks, projected to reach 147,000 by 2040. The structure is 257 ft (78.3 m) long and 90 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesI77 Sbl
CrossesI85
Location0.9 Mi. N. Jct.Lasalle ST
RouteInterstate 77
Coordinates35.27294, -80.84494
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating64.9 US tons
Inventory rating38.9 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length257 ft (78.3 m)
Longest span85 ft (25.9 m)
Deck width90 ft (27.4 m)
Roadway width55 ft (16.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic73,500 (2019)
Projected traffic147,000 by 2040
Trucks16%
Lanes on structure5
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.9 mi (3 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I77 Sbl over I85 built?

It was built in 1970, making it 55 years old in 2025. It was reconstructed in 1989.

What condition is I77 Sbl over I85 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 August 2024.

How much traffic does I77 Sbl over I85 carry?

About 73,500 vehicles per day (2019 count), of which roughly 16% are trucks.

How long is I77 Sbl over I85?

The structure is 257 ft (78.3 m) long with a longest span of 85 ft (25.9 m) and a deck 90 ft wide.

Who owns I77 Sbl over I85?

It is owned by the State Highway Agency.