US Bridges

Nfa A608 over Rock Creek

Fair

Unicoi County, Tennessee · Near Erwin · Structure no. 860A2540001

Built
1993
32 years old
Condition
Fair
inspected July 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
27 ft
1 main span
Daily traffic
160
2020 count
Owner
City
City or Municipal Highway Agency

About this bridge

Nfa A608 over Rock Creek is a prestressed concrete box beam or girders - multiple carrying Nfa A608 over Rock Creek in Unicoi County, Tennessee. It was built in 1993, so it is 32 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 160 vehicles a day, roughly 2% of them trucks, projected to reach 256 by 2040. The structure is 27 ft (8.2 m) long and 28 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesNfa A608
CrossesRock Creek
LocationNear Erwin
RouteCity Street 608
CountyUnicoi County
StateTennessee
Coordinates36.15313, -82.38803
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than 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 rating98.2 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length27 ft (8.2 m)
Longest span25 ft (7.6 m)
Deck width28 ft (8.5 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic160 (2020)
Projected traffic256 by 2040
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
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 statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa A608 over Rock Creek built?

It was built in 1993, making it 32 years old in 2025.

What condition is Nfa A608 over Rock 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 July 2024.

How much traffic does Nfa A608 over Rock Creek carry?

About 160 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is Nfa A608 over Rock Creek?

The structure is 27 ft (8.2 m) long with a longest span of 25 ft (7.6 m) and a deck 28 ft wide.

Who owns Nfa A608 over Rock Creek?

It is owned by the City or Municipal Highway Agency.