US Bridges

S-40-1581 over Forest Lake

Fair

Richland County, South Carolina · 5 MI NE of Columbia · Structure no. 000000000008587

Built
1992
33 years old
Condition
Fair
inspected November 2024
Type
Slab
Prestressed Concrete
Length
100 ft
3 main spans
Daily traffic
400
2023 count
Owner
State
State Highway Agency

About this bridge

S-40-1581 over Forest Lake is a prestressed concrete slab carrying S-40-1581 over Forest Lake in Richland County, South Carolina. It was built in 1992, so it is 33 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 5 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 400 vehicles a day, roughly 4% of them trucks, projected to reach 528 by 2043. The structure is 100 ft (30.5 m) long and 33 ft wide.

Location

Open in Google Maps
CarriesS-40-1581
CrossesForest Lake
Location5 MI NE of Columbia
RouteState Highway 1581
CountyRichland County
StateSouth Carolina
Coordinates34.03594, -80.95199
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
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.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating53.9 US tons
Inventory rating21.8 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length100 ft (30.5 m)
Longest span40 ft (12.2 m)
Deck width33 ft (10.1 m)
Roadway width29 ft (8.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic400 (2023)
Projected traffic528 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$160,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was S-40-1581 over Forest Lake built?

It was built in 1992, making it 33 years old in 2025.

What condition is S-40-1581 over Forest Lake 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 November 2024.

How much traffic does S-40-1581 over Forest Lake carry?

About 400 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is S-40-1581 over Forest Lake?

The structure is 100 ft (30.5 m) long with a longest span of 40 ft (12.2 m) and a deck 33 ft wide.

Who owns S-40-1581 over Forest Lake?

It is owned by the State Highway Agency.