US Bridges

I 280N (re Al) over 280/101 Interchange

Fair

San Francisco County, California · 04-SF-280-R4.07R-SF · Structure no. 34 0133R

Built
1960
65 years old
Condition
Fair
inspected March 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
494 ft
5 main spans
Daily traffic
170,000
2019 count
Owner
State
State Highway Agency

About this bridge

I 280N (re Al) over 280/101 Interchange is a concrete continuous box beam or girders - multiple carrying I 280N (re Al) over 280/101 Interchange in San Francisco County, California. It was built in 1960, so it is 65 years old, older than the California average of 54.8 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 170,000 vehicles a day, roughly 1% of them trucks, projected to reach 238,394 by 2044. The structure is 494 ft (150.6 m) long and 73 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesI 280N (re Al)
Crosses280/101 Interchange
Location04-SF-280-R4.07R-SF
RouteInterstate 280
CountySan Francisco County
StateCalifornia
Coordinates37.7335, -122.41116
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 2024
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 geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadUnknown
Structure length494 ft (150.6 m)
Longest span100 ft (30.5 m)
Deck width73 ft (22.3 m)
Roadway width70 ft (21.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic170,000 (2019)
Projected traffic238,394 by 2044
Trucks1%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesOther
Detour if closed3.1 mi (5 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 I 280N (re Al) over 280/101 Interchange built?

It was built in 1960, making it 65 years old in 2025.

What condition is I 280N (re Al) over 280/101 Interchange 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 March 2024.

How much traffic does I 280N (re Al) over 280/101 Interchange carry?

About 170,000 vehicles per day (2019 count), of which roughly 1% are trucks.

How long is I 280N (re Al) over 280/101 Interchange?

The structure is 494 ft (150.6 m) long with a longest span of 100 ft (30.5 m) and a deck 73 ft wide.

Who owns I 280N (re Al) over 280/101 Interchange?

It is owned by the State Highway Agency.