US Bridges

Nfa A763 over West Blackburn Fork

Fair

Putnam County, Tennessee · 2MI North of SR 24 · Structure no. 710A7630003

Built
1986
39 years old
Condition
Fair
inspected August 2024
Type
Culvert
Concrete Continuous
Length
43 ft
3 main spans
Daily traffic
370
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa A763 over West Blackburn Fork is a concrete continuous culvert carrying Nfa A763 over West Blackburn Fork in Putnam County, Tennessee. It was built in 1986, so it is 39 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 370 vehicles a day, roughly 2% of them trucks, projected to reach 592 by 2042. The structure is 43 ft (13.1 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesNfa A763
CrossesWest Blackburn Fork
Location2MI North of SR 24
RouteCounty Highway 0A970
CountyPutnam County
StateTennessee
Coordinates36.19613, -85.58397
Functional classUrban 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 protection4 PoorAdvanced section loss, deterioration, spalling or scour.
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 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 rating48.6 US tons
Inventory rating28.9 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length43 ft (13.1 m)
Longest span12 ft (3.7 m)
Deck width26 ft (7.9 m)
Roadway width22 ft (6.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic370 (2020)
Projected traffic592 by 2042
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$97,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa A763 over West Blackburn Fork built?

It was built in 1986, making it 39 years old in 2025.

What condition is Nfa A763 over West Blackburn Fork 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 A763 over West Blackburn Fork carry?

About 370 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is Nfa A763 over West Blackburn Fork?

The structure is 43 ft (13.1 m) long with a longest span of 12 ft (3.7 m) and a deck 26 ft wide.

Who owns Nfa A763 over West Blackburn Fork?

It is owned by the County Highway Agency.