US Bridges

C-32-5606 over Koon Branch

PoorPosted for load

Lexington County, South Carolina · 2MI S of Irmo · Structure no. 000000000006541

Built
1974
51 years old
Condition
Poor
inspected June 2024
Type
Slab
Concrete
Length
30 ft
2 main spans
Daily traffic
150
2023 count
Owner
County
County Highway Agency

About this bridge

C-32-5606 over Koon Branch is a concrete slab carrying C-32-5606 over Koon Branch in Lexington County, South Carolina. It was built in 1974, so it is 51 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 150 vehicles a day, roughly 5% of them trucks, projected to reach 192 by 2043. The structure is 30 ft (9.1 m) long and 28 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesC-32-5606
CrossesKoon Branch
Location2MI S of Irmo
RouteCounty Highway 5606
Coordinates34.06389, -81.18417
Functional classUrban Local

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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating35.7 US tons
Inventory rating21.4 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans2
Design loadH 10
Structure length30 ft (9.1 m)
Longest span15 ft (4.6 m)
Deck width28 ft (8.4 m)
Roadway width26 ft (8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic150 (2023)
Projected traffic192 by 2043
Trucks5%
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

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$53,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was C-32-5606 over Koon Branch built?

It was built in 1974, making it 51 years old in 2025.

What condition is C-32-5606 over Koon Branch 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 June 2024.

How much traffic does C-32-5606 over Koon Branch carry?

About 150 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is C-32-5606 over Koon Branch?

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 C-32-5606 over Koon Branch?

It is owned by the County Highway Agency.