US Bridges

Sc 402 over Alligator Creek

Good

Berkeley County, South Carolina · 11.9MI SE Moncks Crn · Structure no. 000000000001600

Built
1949
76 years old
Condition
Good
inspected September 2023
Type
Culvert
Concrete
Length
31 ft
3 main spans
Daily traffic
3,300
2023 count
Owner
State
State Highway Agency

About this bridge

Sc 402 over Alligator Creek is a concrete culvert carrying Sc 402 over Alligator Creek in Berkeley County, South Carolina. It was built in 1949, so it is 76 years old, older than the South Carolina average of 48 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 3,300 vehicles a day, roughly 16% of them trucks, projected to reach 4,818 by 2043. The structure is 31 ft (9.6 m) long and 34 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesSc 402
CrossesAlligator Creek
Location11.9MI SE Moncks Crn
RouteState Highway 402
Coordinates33.13426, -79.82357
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating39.7 US tons
Inventory rating23.6 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans3
Design loadH 15
Structure length31 ft (9.6 m)
Longest span10 ft (3 m)
Deck width34 ft (10.3 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,300 (2023)
Projected traffic4,818 by 2043
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Sc 402 over Alligator Creek built?

It was built in 1949, making it 76 years old in 2025.

What condition is Sc 402 over Alligator Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in September 2023.

How much traffic does Sc 402 over Alligator Creek carry?

About 3,300 vehicles per day (2023 count), of which roughly 16% are trucks.

How long is Sc 402 over Alligator Creek?

The structure is 31 ft (9.6 m) long with a longest span of 10 ft (3 m) and a deck 34 ft wide.

Who owns Sc 402 over Alligator Creek?

It is owned by the State Highway Agency.