US Bridges

I77 over Irwin Creek

Fair

Mecklenburg County, North Carolina · 0.7 Mi.S.Jct I277&NC16 · Structure no. 000000001190248

Built
1972
53 years old
Condition
Fair
inspected September 2024
Type
Culvert
Concrete Continuous
Length
89 ft
4 main spans
Daily traffic
133,000
2019 count
Owner
State
State Highway Agency

About this bridge

I77 over Irwin Creek is a concrete continuous culvert carrying I77 over Irwin Creek in Mecklenburg County, North Carolina. It was built in 1972, so it is 53 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 133,000 vehicles a day, roughly 16% of them trucks, projected to reach 266,000 by 2040. The structure is 89 ft (27.1 m) long. If it were closed, the detour would be 0.6 mi (1 km).

CarriesI77
CrossesIrwin Creek
Location0.7 Mi.S.Jct I277&NC16
RouteInterstate 77
Coordinates35.23923, -80.85242
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46 US tons
Inventory rating35.9 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans4
Design loadHS 20 + Mod
Structure length89 ft (27.1 m)
Longest span13 ft (3.9 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic133,000 (2019)
Projected traffic266,000 by 2040
Trucks16%
Lanes on structure12
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was I77 over Irwin Creek built?

It was built in 1972, making it 53 years old in 2025.

What condition is I77 over Irwin Creek 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 September 2024.

How much traffic does I77 over Irwin Creek carry?

About 133,000 vehicles per day (2019 count), of which roughly 16% are trucks.

How long is I77 over Irwin Creek?

The structure is 89 ft (27.1 m) long with a longest span of 13 ft (3.9 m).

Who owns I77 over Irwin Creek?

It is owned by the State Highway Agency.