US Bridges

S-18-22 over Platt Branch

Fair

Dorchester County, South Carolina · 5MI NW Sumrvl · Structure no. 000000000007103

Built
1978
47 years old
Condition
Fair
inspected April 2023
Type
Slab
Concrete
Length
45 ft
3 main spans
Daily traffic
13,800
2023 count
Owner
State
State Highway Agency

About this bridge

S-18-22 over Platt Branch is a concrete slab carrying S-18-22 over Platt Branch in Dorchester County, South Carolina. It was built in 1978, so it is 47 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 13,800 vehicles a day, roughly 7% of them trucks, projected to reach 16,836 by 2043. The structure is 45 ft (13.7 m) long and 28 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesS-18-22
CrossesPlatt Branch
Location5MI NW Sumrvl
RouteState Highway 22
Coordinates33.05325, -80.25422
Functional classUrban Minor Arterial

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 protection7 GoodSome minor problems.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.1 US tons
Inventory rating27.4 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans3
Design loadH 15
Structure length45 ft (13.7 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 traffic13,800 (2023)
Projected traffic16,836 by 2043
Trucks7%
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 proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$219,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was S-18-22 over Platt Branch built?

It was built in 1978, making it 47 years old in 2025.

What condition is S-18-22 over Platt Branch 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 April 2023.

How much traffic does S-18-22 over Platt Branch carry?

About 13,800 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is S-18-22 over Platt Branch?

The structure is 45 ft (13.7 m) long with a longest span of 15 ft (4.6 m) and a deck 28 ft wide.

Who owns S-18-22 over Platt Branch?

It is owned by the State Highway Agency.