US Bridges

Coburn Mtn RD over Isbell Branch

Good

Colbert County, Alabama · Coburn Mtn Off Lagrange · Structure no. 015464

Built
1991
34 years old
Condition
Good
inspected January 2024
Type
Culvert
Concrete
Length
24 ft
2 main spans
Daily traffic
285
1985 count
Owner
County
County Highway Agency

About this bridge

Coburn Mtn RD over Isbell Branch is a concrete culvert carrying Coburn Mtn RD over Isbell Branch in Colbert County, Alabama. It was built in 1991, so it is 34 years old, younger than the Alabama average of 51.1 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 285 vehicles a day, roughly 1% of them trucks, projected to reach 401 by 2044. The structure is 24 ft (7.3 m) long. If it were closed, the detour would be 8.1 mi (13 km).

CarriesCoburn Mtn RD
CrossesIsbell Branch
LocationCoburn Mtn Off Lagrange
RouteCounty Highway 77
StateAlabama
Coordinates34.63645, -87.61433
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 protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating98 US tons
Inventory rating89.6 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length24 ft (7.3 m)
Longest span12 ft (3.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic285 (1985)
Projected traffic401 by 2044
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 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 proposedNone recorded
Estimated improvement cost$490,000 (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Coburn Mtn RD over Isbell Branch built?

It was built in 1991, making it 34 years old in 2025.

What condition is Coburn Mtn RD over Isbell Branch 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 January 2024.

How much traffic does Coburn Mtn RD over Isbell Branch carry?

About 285 vehicles per day (1985 count), of which roughly 1% are trucks.

How long is Coburn Mtn RD over Isbell Branch?

The structure is 24 ft (7.3 m) long with a longest span of 12 ft (3.7 m).

Who owns Coburn Mtn RD over Isbell Branch?

It is owned by the County Highway Agency.