US Bridges

US421 Sbl over Yadkin River

Fair

Forsyth County, North Carolina · 1.1 Mi. S. Jct. SR1301 · Structure no. 000000000670051

Built
1973
52 years old
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
621 ft
5 main spans
Daily traffic
12,000
2017 count
Owner
State
State Highway Agency

About this bridge

US421 Sbl over Yadkin River is a steel continuous stringer/multi-beam or girder carrying US421 Sbl over Yadkin River in Forsyth County, North Carolina. It was built in 1973, so it is 52 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 12,000 vehicles a day, roughly 14% of them trucks, projected to reach 27,000 by 2040. The structure is 621 ft (189.2 m) long and 42 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

CarriesUS421 Sbl
CrossesYadkin River
Location1.1 Mi. S. Jct. SR1301
RouteU.S. Route 421
Coordinates36.1034, -80.50814
Functional classRural Principal Arterial - Other

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.
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 inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating47 US tons
Inventory rating28 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5 (+5 approach)
Design loadHS 20 + Mod
Structure length621 ft (189.2 m)
Longest span80 ft (24.3 m)
Deck width42 ft (12.8 m)
Roadway width39 ft (12 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,000 (2017)
Projected traffic27,000 by 2040
Trucks14%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was US421 Sbl over Yadkin River built?

It was built in 1973, making it 52 years old in 2025.

What condition is US421 Sbl over Yadkin River 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 July 2024.

How much traffic does US421 Sbl over Yadkin River carry?

About 12,000 vehicles per day (2017 count), of which roughly 14% are trucks.

How long is US421 Sbl over Yadkin River?

The structure is 621 ft (189.2 m) long with a longest span of 80 ft (24.3 m) and a deck 42 ft wide.

Who owns US421 Sbl over Yadkin River?

It is owned by the State Highway Agency.