US Bridges

Nfa A018 over Johnson Creek

Fair

Decatur County, Tennessee · 2.1 MI W JCT SR20&SR69 · Structure no. 200A0180001

Built
1977
48 years old
Condition
Fair
inspected January 2024
Type
Culvert
Concrete Continuous
Length
39 ft
3 main spans
Daily traffic
40
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa A018 over Johnson Creek is a concrete continuous culvert carrying Nfa A018 over Johnson Creek in Decatur County, Tennessee. It was built in 1977, so it is 48 years old, older 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 40 vehicles a day, roughly 1% of them trucks, projected to reach 64 by 2042. The structure is 39 ft (11.9 m) long and 32 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesNfa A018
CrossesJohnson Creek
Location2.1 MI W JCT SR20&SR69
RouteCounty Highway 18
Coordinates35.64842, -88.16397
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 inspectionJanuary 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 geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating42.5 US tons
Inventory rating24.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length39 ft (11.9 m)
Longest span12 ft (3.7 m)
Deck width32 ft (9.8 m)
Roadway width28 ft (8.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2020)
Projected traffic64 by 2042
Trucks1%
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 statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa A018 over Johnson Creek built?

It was built in 1977, making it 48 years old in 2025.

What condition is Nfa A018 over Johnson Creek 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 Nfa A018 over Johnson Creek carry?

About 40 vehicles per day (2020 count), of which roughly 1% are trucks.

How long is Nfa A018 over Johnson Creek?

The structure is 39 ft (11.9 m) long with a longest span of 12 ft (3.7 m) and a deck 32 ft wide.

Who owns Nfa A018 over Johnson Creek?

It is owned by the County Highway Agency.