US Bridges

N280-N35 Cnntr Rmp over Interstate 280

Fair

San Mateo County, California · 04-SM-035-L23.00-SBR · Structure no. 35 0200G

Built
1967
58 years old
Condition
Fair
inspected July 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete Continuous
Length
370 ft
2 main spans
Daily traffic
5,600
2005 count
Owner
State
State Highway Agency

About this bridge

N280-N35 Cnntr Rmp over Interstate 280 is a prestressed concrete continuous box beam or girders - multiple carrying N280-N35 Cnntr Rmp over Interstate 280 in San Mateo County, California. It was built in 1967, so it is 58 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 5,600 vehicles a day, roughly 2% of them trucks, projected to reach 7,482 by 2040. The structure is 370 ft (112.8 m) long and 41 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesN280-N35 Cnntr Rmp
CrossesInterstate 280
Location04-SM-035-L23.00-SBR
RouteState Highway 35
Coordinates37.60427, -122.42733
Functional classUrban Other Principal Arterial

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.
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 inspectionJuly 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 geometry9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating110 US tons
Inventory rating35.7 US tons

Structure

MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length370 ft (112.8 m)
Longest span193 ft (58.7 m)
Deck width41 ft (12.4 m)
Roadway width37 ft (11.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,600 (2005)
Projected traffic7,482 by 2040
Trucks2%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemYes

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 N280-N35 Cnntr Rmp over Interstate 280 built?

It was built in 1967, making it 58 years old in 2025.

What condition is N280-N35 Cnntr Rmp over Interstate 280 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 July 2023.

How much traffic does N280-N35 Cnntr Rmp over Interstate 280 carry?

About 5,600 vehicles per day (2005 count), of which roughly 2% are trucks.

How long is N280-N35 Cnntr Rmp over Interstate 280?

The structure is 370 ft (112.8 m) long with a longest span of 193 ft (58.7 m) and a deck 41 ft wide.

Who owns N280-N35 Cnntr Rmp over Interstate 280?

It is owned by the State Highway Agency.