US Bridges

Nfa A446 over I75 Sbl

FairPosted for load

McMinn County, Tennessee · 4 MI from SR2 · Structure no. 54I00750051

Built
1972
53 years old
Condition
Fair
inspected April 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
227 ft
3 main spans
Daily traffic
870
2021 count
Owner
State
State Highway Agency

About this bridge

Nfa A446 over I75 Sbl is a prestressed concrete box beam or girders - multiple carrying Nfa A446 over I75 Sbl in McMinn County, Tennessee. It was built in 1972, so it is 53 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 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 870 vehicles a day, roughly 3% of them trucks, projected to reach 1,392 by 2042. The structure is 227 ft (69.2 m) long and 32 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesNfa A446
CrossesI75 Sbl
Location4 MI from SR2
RouteCounty Highway 5408
Coordinates35.4486, -84.6675
Functional classRural Minor Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length227 ft (69.2 m)
Longest span117 ft (35.7 m)
Deck width32 ft (9.8 m)
Roadway width29 ft (8.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic870 (2021)
Projected traffic1,392 by 2042
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Nfa A446 over I75 Sbl built?

It was built in 1972, making it 53 years old in 2025.

What condition is Nfa A446 over I75 Sbl 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 April 2024.

How much traffic does Nfa A446 over I75 Sbl carry?

About 870 vehicles per day (2021 count), of which roughly 3% are trucks.

How long is Nfa A446 over I75 Sbl?

The structure is 227 ft (69.2 m) long with a longest span of 117 ft (35.7 m) and a deck 32 ft wide.

Who owns Nfa A446 over I75 Sbl?

It is owned by the State Highway Agency.