US Bridges

Nfa A556 over Riley Creek

Good

Roane County, Tennessee · E Off SR58-.8 M N of SR72 · Structure no. 730A3080001

Built
1996
29 years old
Condition
Good
inspected April 2023
Type
Box Beam or Girders - Single or Spread
Prestressed Concrete
Length
46 ft
1 main span
Daily traffic
840
2020 count
Owner
County
County Highway Agency

About this bridge

Nfa A556 over Riley Creek is a prestressed concrete box beam or girders - single or spread carrying Nfa A556 over Riley Creek in Roane County, Tennessee. It was built in 1996, so it is 29 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 840 vehicles a day, roughly 2% of them trucks, projected to reach 1,344 by 2041. The structure is 46 ft (14 m) long and 24 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesNfa A556
CrossesRiley Creek
LocationE Off SR58-.8 M N of SR72
RouteCounty Highway 556
CountyRoane County
StateTennessee
Coordinates35.81088, -84.55241
Functional classRural Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating62.5 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length46 ft (14 m)
Longest span43 ft (13.1 m)
Deck width24 ft (7.4 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic840 (2020)
Projected traffic1,344 by 2041
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 A556 over Riley Creek built?

It was built in 1996, making it 29 years old in 2025.

What condition is Nfa A556 over Riley 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 April 2023.

How much traffic does Nfa A556 over Riley Creek carry?

About 840 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is Nfa A556 over Riley Creek?

The structure is 46 ft (14 m) long with a longest span of 43 ft (13.1 m) and a deck 24 ft wide.

Who owns Nfa A556 over Riley Creek?

It is owned by the County Highway Agency.