US Bridges

S-16-30 over Middle Swamp

Fair

Darlington County, South Carolina · 8 MI S Darlington · Structure no. 000000000008824

Built
1995
30 years old
Condition
Fair
inspected February 2025
Type
Slab
Concrete Continuous
Length
90 ft
3 main spans
Daily traffic
3,400
2023 count
Owner
State
State Highway Agency

About this bridge

S-16-30 over Middle Swamp is a concrete continuous slab carrying S-16-30 over Middle Swamp in Darlington County, South Carolina. It was built in 1995, so it is 30 years old, younger than the South Carolina average of 48 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 3,400 vehicles a day, roughly 10% of them trucks, projected to reach 2,040 by 2043. The structure is 90 ft (27.4 m) long and 35 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesS-16-30
CrossesMiddle Swamp
Location8 MI S Darlington
RouteState Highway 30
CountyDarlington County
StateSouth Carolina
Coordinates34.18504, -79.91392
Functional classUrban Collector

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.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating52.1 US tons
Inventory rating40.3 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 25 or greater
Structure length90 ft (27.4 m)
Longest span30 ft (9.1 m)
Deck width35 ft (10.6 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,400 (2023)
Projected traffic2,040 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 S-16-30 over Middle Swamp built?

It was built in 1995, making it 30 years old in 2025.

What condition is S-16-30 over Middle Swamp 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 February 2025.

How much traffic does S-16-30 over Middle Swamp carry?

About 3,400 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is S-16-30 over Middle Swamp?

The structure is 90 ft (27.4 m) long with a longest span of 30 ft (9.1 m) and a deck 35 ft wide.

Who owns S-16-30 over Middle Swamp?

It is owned by the State Highway Agency.