US Bridges

US 31 over Gum Swamp Branch

Fair

Chilton County, Alabama · 2.7 MI S Thorsby · Structure no. 003949

Built
1924
101 years old, rebuilt 1951
Condition
Fair
inspected January 2024
Type
Tee Beam
Concrete
Length
103 ft
3 main spans
Daily traffic
6,590
2016 count
Owner
State
State Highway Agency

About this bridge

US 31 over Gum Swamp Branch is a concrete tee beam carrying US 31 over Gum Swamp Branch in Chilton County, Alabama. It was built in 1924 and reconstructed in 1951, so it is 101 years old, older than the Alabama average of 51.1 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 6,590 vehicles a day, roughly 8% of them trucks, projected to reach 8,465 by 2044. The structure is 103 ft (31.5 m) long and 43 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesUS 31
CrossesGum Swamp Branch
Location2.7 MI S Thorsby
RouteU.S. Route 31
CountyChilton County
StateAlabama
Coordinates32.88993, -86.67693
Functional classRural Major 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.1 US tons
Inventory rating34.2 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length103 ft (31.5 m)
Longest span34 ft (10.5 m)
Deck width43 ft (13.1 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,590 (2016)
Projected traffic8,465 by 2044
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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$1.3 million (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 31 over Gum Swamp Branch built?

It was built in 1924, making it 101 years old in 2025. It was reconstructed in 1951.

What condition is US 31 over Gum Swamp 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 January 2024.

How much traffic does US 31 over Gum Swamp Branch carry?

About 6,590 vehicles per day (2016 count), of which roughly 8% are trucks.

How long is US 31 over Gum Swamp Branch?

The structure is 103 ft (31.5 m) long with a longest span of 34 ft (10.5 m) and a deck 43 ft wide.

Who owns US 31 over Gum Swamp Branch?

It is owned by the State Highway Agency.