US Bridges

Nfa A672 over Knob Creek

Fair

Washington County, Tennessee · E Off US11E-N of SR36 JCT · Structure no. 900A6720001

Built
1960
65 years old
Condition
Fair
inspected June 2024
Type
Tee Beam
Concrete
Length
236 ft
5 main spans
Daily traffic
2,230
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa A672 over Knob Creek is a concrete tee beam carrying Nfa A672 over Knob Creek in Washington County, Tennessee. It was built in 1960, so it is 65 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 2,230 vehicles a day, roughly 2% of them trucks, projected to reach 3,568 by 2042. The structure is 236 ft (72 m) long and 22 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesNfa A672
CrossesKnob Creek
LocationE Off US11E-N of SR36 JCT
RouteCounty Highway 672
CountyWashington County
StateTennessee
Coordinates36.3845, -82.36263
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 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 geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating46.7 US tons
Inventory rating27.9 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans5
Design loadH 15
Structure length236 ft (72 m)
Longest span46 ft (14 m)
Deck width22 ft (6.6 m)
Roadway width18 ft (5.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,230 (2020)
Projected traffic3,568 by 2042
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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$1.4 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa A672 over Knob Creek built?

It was built in 1960, making it 65 years old in 2025.

What condition is Nfa A672 over Knob 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 June 2024.

How much traffic does Nfa A672 over Knob Creek carry?

About 2,230 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is Nfa A672 over Knob Creek?

The structure is 236 ft (72 m) long with a longest span of 46 ft (14 m) and a deck 22 ft wide.

Who owns Nfa A672 over Knob Creek?

It is owned by the County Highway Agency.