US Bridges

I85 US15 Sbl over SR1637 & Southern RR

Fair

Durham County, North Carolina · 0.33 Mi. N. Jct. SR1632 · Structure no. 000000000630218

Built
1965
60 years old, rebuilt 1997
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
209 ft
4 main spans
Daily traffic
25,750
2019 count
Owner
State
State Highway Agency

About this bridge

I85 US15 Sbl over SR1637 & Southern RR is a steel stringer/multi-beam or girder carrying I85 US15 Sbl over SR1637 & Southern RR in Durham County, North Carolina. It was built in 1965 and reconstructed in 1997, so it is 60 years old, older than the North Carolina average of 38.7 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 25,750 vehicles a day, roughly 16% of them trucks, projected to reach 51,500 by 2040. The structure is 209 ft (63.7 m) long and 43 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesI85 US15 Sbl
CrossesSR1637 & Southern RR
Location0.33 Mi. N. Jct. SR1632
RouteInterstate 85
CountyDurham County
StateNorth Carolina
Coordinates36.04869, -78.81095
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating88 US tons
Inventory rating52.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length209 ft (63.7 m)
Longest span51 ft (15.5 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25,750 (2019)
Projected traffic51,500 by 2040
Trucks16%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed0.6 mi (1 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I85 US15 Sbl over SR1637 & Southern RR built?

It was built in 1965, making it 60 years old in 2025. It was reconstructed in 1997.

What condition is I85 US15 Sbl over SR1637 & Southern RR 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 2023.

How much traffic does I85 US15 Sbl over SR1637 & Southern RR carry?

About 25,750 vehicles per day (2019 count), of which roughly 16% are trucks.

How long is I85 US15 Sbl over SR1637 & Southern RR?

The structure is 209 ft (63.7 m) long with a longest span of 51 ft (15.5 m) and a deck 43 ft wide.

Who owns I85 US15 Sbl over SR1637 & Southern RR?

It is owned by the State Highway Agency.