US Bridges

S-45-85 over Boggy Swamp

PoorPosted for load

Williamsburg County, South Carolina · 5.5 MI W Hemingway · Structure no. 000000000004673

Built
1965
60 years old
Condition
Poor
inspected August 2023
Type
Slab
Concrete
Length
30 ft
2 main spans
Daily traffic
300
2023 count
Owner
State
State Highway Agency

About this bridge

S-45-85 over Boggy Swamp is a concrete slab carrying S-45-85 over Boggy Swamp in Williamsburg County, South Carolina. It was built in 1965, so it is 60 years old, older than the South Carolina average of 48 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 300 vehicles a day, roughly 9% of them trucks, projected to reach 438 by 2043. The structure is 30 ft (9.1 m) long and 28 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesS-45-85
CrossesBoggy Swamp
Location5.5 MI W Hemingway
RouteState Highway 85
CountyWilliamsburg County
StateSouth Carolina
Coordinates33.76661, -79.55219
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating6.8 US tons
Inventory rating1.4 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans2
Design loadH 15
Structure length30 ft (9.1 m)
Longest span15 ft (4.6 m)
Deck width28 ft (8.4 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic300 (2023)
Projected traffic438 by 2043
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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-45-85 over Boggy Swamp built?

It was built in 1965, making it 60 years old in 2025.

What condition is S-45-85 over Boggy Swamp in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2023.

How much traffic does S-45-85 over Boggy Swamp carry?

About 300 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is S-45-85 over Boggy Swamp?

The structure is 30 ft (9.1 m) long with a longest span of 15 ft (4.6 m) and a deck 28 ft wide.

Who owns S-45-85 over Boggy Swamp?

It is owned by the State Highway Agency.