US Bridges

US21 SR 2108 over I77

Fair

Mecklenburg County, North Carolina · 0.56 Mi. W. Jct. SR2691 · Structure no. 000000001190323

Built
1975
50 years old, rebuilt 2013
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
298 ft
2 main spans
Daily traffic
16,500
2022 count
Owner
State
State Highway Agency

About this bridge

US21 SR 2108 over I77 is a steel continuous stringer/multi-beam or girder carrying US21 SR 2108 over I77 in Mecklenburg County, North Carolina. It was built in 1975 and reconstructed in 2013, so it is 50 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 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 16,500 vehicles a day, roughly 12% of them trucks, projected to reach 33,000 by 2040. The structure is 298 ft (90.8 m) long and 102 ft wide. If it were closed, the detour would be 2.5 mi (4 km).

Location

Open in Google Maps
CarriesUS21 SR 2108
CrossesI77
Location0.56 Mi. W. Jct. SR2691
RouteU.S. Route 21
CountyMecklenburg County
StateNorth Carolina
Coordinates35.30733, -80.84802
Functional classUrban Other Principal Arterial

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.
Superstructure7 GoodSome minor problems.
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 geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70 US tons
Inventory rating42 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20 + Mod
Structure length298 ft (90.8 m)
Longest span112 ft (34.1 m)
Deck width102 ft (31 m)
Roadway width87 ft (26.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,500 (2022)
Projected traffic33,000 by 2040
Trucks12%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed2.5 mi (4 km)
TollOn a free road
National Highway SystemYes

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 US21 SR 2108 over I77 built?

It was built in 1975, making it 50 years old in 2025. It was reconstructed in 2013.

What condition is US21 SR 2108 over I77 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 US21 SR 2108 over I77 carry?

About 16,500 vehicles per day (2022 count), of which roughly 12% are trucks.

How long is US21 SR 2108 over I77?

The structure is 298 ft (90.8 m) long with a longest span of 112 ft (34.1 m) and a deck 102 ft wide.

Who owns US21 SR 2108 over I77?

It is owned by the State Highway Agency.