US Bridges

Nfa D771 over Rock Creek

Fair

Hamilton County, Tennessee · .5 MI West of US 27 · Structure no. 330D7710001

Built
1955
70 years old
Condition
Fair
inspected January 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
146 ft
3 main spans
Daily traffic
729
2021 count
Owner
County
County Highway Agency

About this bridge

Nfa D771 over Rock Creek is a steel continuous stringer/multi-beam or girder carrying Nfa D771 over Rock Creek in Hamilton County, Tennessee. It was built in 1955, so it is 70 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 729 vehicles a day, roughly 3% of them trucks, projected to reach 1,166 by 2042. The structure is 146 ft (44.5 m) long and 30 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesNfa D771
CrossesRock Creek
Location.5 MI West of US 27
RouteCounty Highway 5778
CountyHamilton County
StateTennessee
Coordinates35.38315, -85.12115
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44 US tons
Inventory rating34 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length146 ft (44.5 m)
Longest span65 ft (19.8 m)
Deck width30 ft (9.2 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic729 (2021)
Projected traffic1,166 by 2042
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$1.1 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nfa D771 over Rock Creek built?

It was built in 1955, making it 70 years old in 2025.

What condition is Nfa D771 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 January 2024.

How much traffic does Nfa D771 over Rock Creek carry?

About 729 vehicles per day (2021 count), of which roughly 3% are trucks.

How long is Nfa D771 over Rock Creek?

The structure is 146 ft (44.5 m) long with a longest span of 65 ft (19.8 m) and a deck 30 ft wide.

Who owns Nfa D771 over Rock Creek?

It is owned by the County Highway Agency.