US Bridges

Rockbridge Road over I-285 (sr 407)

Fair

DeKalb County, Georgia · 2.8 MI S of Clarkston · Structure no. 000000008901180

Built
1966
59 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
272 ft
4 main spans
Daily traffic
1,740
2024 count
Owner
State
State Highway Agency

About this bridge

Rockbridge Road over I-285 (sr 407) is a steel stringer/multi-beam or girder carrying Rockbridge Road over I-285 (sr 407) in DeKalb County, Georgia. It was built in 1966, so it is 59 years old, older than the Georgia average of 47.5 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 1,740 vehicles a day, roughly 1% of them trucks, projected to reach 3,303 by 2031. The structure is 272 ft (82.9 m) long and 36 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesRockbridge Road
CrossesI-285 (sr 407)
Location2.8 MI S of Clarkston
RouteCounty Highway 848
CountyDeKalb County
StateGeorgia
Coordinates33.78312, -84.24551
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating44 US tons
Inventory rating25.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length272 ft (82.9 m)
Longest span83 ft (25.3 m)
Deck width36 ft (10.9 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,740 (2024)
Projected traffic3,303 by 2031
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost$1.6 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was Rockbridge Road over I-285 (sr 407) built?

It was built in 1966, making it 59 years old in 2025.

What condition is Rockbridge Road over I-285 (sr 407) 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 June 2024.

How much traffic does Rockbridge Road over I-285 (sr 407) carry?

About 1,740 vehicles per day (2024 count), of which roughly 1% are trucks.

How long is Rockbridge Road over I-285 (sr 407)?

The structure is 272 ft (82.9 m) long with a longest span of 83 ft (25.3 m) and a deck 36 ft wide.

Who owns Rockbridge Road over I-285 (sr 407)?

It is owned by the State Highway Agency.