US Bridges

Nfa B570 over Mad Branch

Fair

Sullivan County, Tennessee · S of SR36 in Kingsport · Structure no. 820B5700001

Built
1968
57 years old
Condition
Fair
inspected March 2024
Type
Culvert
Concrete Continuous
Length
28 ft
3 main spans
Daily traffic
510
2020 count
Owner
City
City or Municipal Highway Agency

About this bridge

Nfa B570 over Mad Branch is a concrete continuous culvert carrying Nfa B570 over Mad Branch in Sullivan County, Tennessee. It was built in 1968, so it is 57 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 510 vehicles a day, roughly 2% of them trucks, projected to reach 816 by 2042. The structure is 28 ft (8.5 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesNfa B570
CrossesMad Branch
LocationS of SR36 in Kingsport
RouteCity Street 570
CountySullivan County
StateTennessee
Coordinates36.53587, -82.53355
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 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
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.5 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadHS 15
Structure length28 ft (8.5 m)
Longest span9 ft (2.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic510 (2020)
Projected traffic816 by 2042
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Nfa B570 over Mad Branch built?

It was built in 1968, making it 57 years old in 2025.

What condition is Nfa B570 over Mad Branch 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 March 2024.

How much traffic does Nfa B570 over Mad Branch carry?

About 510 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is Nfa B570 over Mad Branch?

The structure is 28 ft (8.5 m) long with a longest span of 9 ft (2.7 m).

Who owns Nfa B570 over Mad Branch?

It is owned by the City or Municipal Highway Agency.