US Bridges

Nfa D403 over Little Flat Creek

Fair

Knox County, Tennessee · S of Corryton · Structure no. 470D4030001

Built
1973
52 years old
Condition
Fair
inspected May 2024
Type
Culvert
Steel
Length
31 ft
2 main spans
Daily traffic
60
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa D403 over Little Flat Creek is a steel culvert carrying Nfa D403 over Little Flat Creek in Knox County, Tennessee. It was built in 1973, so it is 52 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.

It carries about 60 vehicles a day, roughly 1% of them trucks, projected to reach 96 by 2040. The structure is 31 ft (9.4 m) long. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesNfa D403
CrossesLittle Flat Creek
LocationS of Corryton
RouteCounty Highway 403
CountyKnox County
StateTennessee
Coordinates36.12385, -83.77492
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 protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating98.2 US tons
Inventory rating26.8 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadH 15
Structure length31 ft (9.4 m)
Longest span16 ft (4.8 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic60 (2020)
Projected traffic96 by 2040
Trucks1%
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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$205,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa D403 over Little Flat Creek built?

It was built in 1973, making it 52 years old in 2025.

What condition is Nfa D403 over Little Flat 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 May 2024.

How much traffic does Nfa D403 over Little Flat Creek carry?

About 60 vehicles per day (2020 count), of which roughly 1% are trucks.

How long is Nfa D403 over Little Flat Creek?

The structure is 31 ft (9.4 m) long with a longest span of 16 ft (4.8 m).

Who owns Nfa D403 over Little Flat Creek?

It is owned by the County Highway Agency.