US Bridges

Nfa 1798 (sa 4315) over Miller Branch

Fair

Humphreys County, Tennessee · 5 Mi. Ne. SR230. · Structure no. 43017980007

Built
1976
49 years old
Condition
Fair
inspected October 2023
Type
Culvert
Concrete Continuous
Length
102 ft
4 main spans
Daily traffic
278
2021 count
Owner
County
County Highway Agency

About this bridge

Nfa 1798 (sa 4315) over Miller Branch is a concrete continuous culvert carrying Nfa 1798 (sa 4315) over Miller Branch in Humphreys County, Tennessee. It was built in 1976, so it is 49 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 278 vehicles a day, roughly 3% of them trucks, projected to reach 445 by 2042. The structure is 102 ft (31.1 m) long and 28 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

CarriesNfa 1798 (sa 4315)
CrossesMiller Branch
Location5 Mi. Ne. SR230.
RouteCounty Highway 1798
Coordinates35.98084, -87.573
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
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.7 US tons
Inventory rating27.9 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadUnknown
Structure length102 ft (31.1 m)
Longest span24 ft (7.3 m)
Deck width28 ft (8.5 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic278 (2021)
Projected traffic445 by 2042
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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$134,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa 1798 (sa 4315) over Miller Branch built?

It was built in 1976, making it 49 years old in 2025.

What condition is Nfa 1798 (sa 4315) over Miller 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 October 2023.

How much traffic does Nfa 1798 (sa 4315) over Miller Branch carry?

About 278 vehicles per day (2021 count), of which roughly 3% are trucks.

How long is Nfa 1798 (sa 4315) over Miller Branch?

The structure is 102 ft (31.1 m) long with a longest span of 24 ft (7.3 m) and a deck 28 ft wide.

Who owns Nfa 1798 (sa 4315) over Miller Branch?

It is owned by the County Highway Agency.