US Bridges

US21 over I77

Fair

Mecklenburg County, North Carolina · 0.15 Mi. E. Jct. SR2195 · Structure no. 000000001190019

Built
1976
49 years old
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
220 ft
3 main spans
Daily traffic
27,000
2018 count
Owner
State
State Highway Agency

About this bridge

US21 over I77 is a steel stringer/multi-beam or girder carrying US21 over I77 in Mecklenburg County, North Carolina. It was built in 1976, so it is 49 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 27,000 vehicles a day, roughly 6% of them trucks, projected to reach 54,000 by 2040. The structure is 220 ft (67 m) long and 82 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesUS21
CrossesI77
Location0.15 Mi. E. Jct. SR2195
RouteU.S. Route 21
CountyMecklenburg County
StateNorth Carolina
Coordinates35.48346, -80.87472
Functional classUrban Minor 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 inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating62.9 US tons
Inventory rating36.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length220 ft (67 m)
Longest span157 ft (47.8 m)
Deck width82 ft (24.9 m)
Roadway width68 ft (20.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic27,000 (2018)
Projected traffic54,000 by 2040
Trucks6%
Lanes on structure5
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

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 over I77 built?

It was built in 1976, making it 49 years old in 2025.

What condition is US21 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 April 2023.

How much traffic does US21 over I77 carry?

About 27,000 vehicles per day (2018 count), of which roughly 6% are trucks.

How long is US21 over I77?

The structure is 220 ft (67 m) long with a longest span of 157 ft (47.8 m) and a deck 82 ft wide.

Who owns US21 over I77?

It is owned by the State Highway Agency.