US Bridges

Nfa A506 over Gilmore Branch

Fair

McNairy County, Tennessee · 7.5 MI S of SR15 · Structure no. 550A5060001

Built
1983
42 years old
Condition
Fair
inspected August 2024
Type
Culvert
Concrete Continuous
Length
39 ft
3 main spans
Daily traffic
30
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa A506 over Gilmore Branch is a concrete continuous culvert carrying Nfa A506 over Gilmore Branch in McNairy County, Tennessee. It was built in 1983, so it is 42 years old, younger than the Tennessee average of 47.4 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 30 vehicles a day, roughly 2% of them trucks, projected to reach 48 by 2040. The structure is 39 ft (11.9 m) long and 27 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesNfa A506
CrossesGilmore Branch
Location7.5 MI S of SR15
RouteCounty Highway 506
CountyMcNairy County
StateTennessee
Coordinates35.12464, -88.67308
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.6 US tons
Inventory rating27.9 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadHS 20
Structure length39 ft (11.9 m)
Longest span12 ft (3.7 m)
Deck width27 ft (8.3 m)
Roadway width23 ft (7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30 (2020)
Projected traffic48 by 2040
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Nfa A506 over Gilmore Branch built?

It was built in 1983, making it 42 years old in 2025.

What condition is Nfa A506 over Gilmore 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 August 2024.

How much traffic does Nfa A506 over Gilmore Branch carry?

About 30 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is Nfa A506 over Gilmore Branch?

The structure is 39 ft (11.9 m) long with a longest span of 12 ft (3.7 m) and a deck 27 ft wide.

Who owns Nfa A506 over Gilmore Branch?

It is owned by the County Highway Agency.