US Bridges

Nfa A254 over Rock Creek

Good

Unicoi County, Tennessee · Near Erwin · Structure no. 860A2540003

Built
1978
47 years old, rebuilt 2024
Condition
Good
inspected July 2024
Type
Slab
Concrete
Length
38 ft
1 main span
Daily traffic
430
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa A254 over Rock Creek is a concrete slab carrying Nfa A254 over Rock Creek in Unicoi County, Tennessee. It was built in 1978 and reconstructed in 2024, so it is 47 years old, younger than the Tennessee average of 47.4 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 430 vehicles a day, roughly 4% of them trucks, projected to reach 688 by 2042. The structure is 38 ft (11.6 m) long and 18 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesNfa A254
CrossesRock Creek
LocationNear Erwin
RouteCounty Highway 254
CountyUnicoi County
StateTennessee
Coordinates36.15429, -82.38869
Functional classUrban Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating52.5 US tons
Inventory rating40.7 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadUnknown
Structure length38 ft (11.6 m)
Longest span35 ft (10.8 m)
Deck width18 ft (5.5 m)
Roadway width17 ft (5.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic430 (2020)
Projected traffic688 by 2042
Trucks4%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 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$254,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa A254 over Rock Creek built?

It was built in 1978, making it 47 years old in 2025. It was reconstructed in 2024.

What condition is Nfa A254 over Rock Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in July 2024.

How much traffic does Nfa A254 over Rock Creek carry?

About 430 vehicles per day (2020 count), of which roughly 4% are trucks.

How long is Nfa A254 over Rock Creek?

The structure is 38 ft (11.6 m) long with a longest span of 35 ft (10.8 m) and a deck 18 ft wide.

Who owns Nfa A254 over Rock Creek?

It is owned by the County Highway Agency.