US Bridges

S-18-86/MT Zion RD over Trib to Indian Field Swp

Good

Dorchester County, South Carolina · 2.9 MI NW ST George · Structure no. 000000000006285

Built
1973
52 years old
Condition
Good
inspected May 2023
Type
Culvert
Concrete
Length
27 ft
3 main spans
Daily traffic
375
2023 count
Owner
State
State Highway Agency

About this bridge

S-18-86/MT Zion RD over Trib to Indian Field Swp is a concrete culvert carrying S-18-86/MT Zion RD over Trib to Indian Field Swp in Dorchester County, South Carolina. It was built in 1973, so it is 52 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 375 vehicles a day, roughly 8% of them trucks, projected to reach 521 by 2043. The structure is 27 ft (8.2 m) long and 90 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesS-18-86/MT Zion RD
CrossesTrib to Indian Field Swp
Location2.9 MI NW ST George
RouteState Highway 86
Coordinates33.22804, -80.58917
Functional classRural Minor 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 inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating107.1 US tons
Inventory rating107.1 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans3
Design loadH 20
Structure length27 ft (8.2 m)
Longest span9 ft (2.7 m)
Deck width90 ft (27.4 m)
Roadway width88 ft (26.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic375 (2023)
Projected traffic521 by 2043
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was S-18-86/MT Zion RD over Trib to Indian Field Swp built?

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

What condition is S-18-86/MT Zion RD over Trib to Indian Field Swp 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 May 2023.

How much traffic does S-18-86/MT Zion RD over Trib to Indian Field Swp carry?

About 375 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is S-18-86/MT Zion RD over Trib to Indian Field Swp?

The structure is 27 ft (8.2 m) long with a longest span of 9 ft (2.7 m) and a deck 90 ft wide.

Who owns S-18-86/MT Zion RD over Trib to Indian Field Swp?

It is owned by the State Highway Agency.