US Bridges

I840 over Natchez Trace & Burns Br

Fair

Williamson County, Tennessee · 1 MI W SR46 · Structure no. 94SR8400028

Built
2012
13 years old
Condition
Fair
inspected January 2025
Type
Box Beam or Girders - Single or Spread
Prestressed Concrete Continuous
Length
340 ft
2 main spans
Daily traffic
22,556
2021 count
Owner
State
State Highway Agency

About this bridge

I840 over Natchez Trace & Burns Br is a prestressed concrete continuous box beam or girders - single or spread carrying I840 over Natchez Trace & Burns Br in Williamson County, Tennessee. It was built in 2012, so it is 13 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 22,556 vehicles a day, roughly 7% of them trucks, projected to reach 34,176 by 2041. The structure is 340 ft (103.6 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI840
CrossesNatchez Trace & Burns Br
Location1 MI W SR46
RouteInterstate 840
Coordinates35.83938, -87.06206
Functional classRural Principal Arterial - Interstate

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJanuary 2025
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 geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHL 93
Structure length340 ft (103.6 m)
Longest span170 ft (51.8 m)
Deck width44 ft (13.4 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic22,556 (2021)
Projected traffic34,176 by 2041
Trucks7%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and waterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was I840 over Natchez Trace & Burns Br built?

It was built in 2012, making it 13 years old in 2025.

What condition is I840 over Natchez Trace & Burns Br 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 2025.

How much traffic does I840 over Natchez Trace & Burns Br carry?

About 22,556 vehicles per day (2021 count), of which roughly 7% are trucks.

How long is I840 over Natchez Trace & Burns Br?

The structure is 340 ft (103.6 m) long with a longest span of 170 ft (51.8 m) and a deck 44 ft wide.

Who owns I840 over Natchez Trace & Burns Br?

It is owned by the State Highway Agency.