US Bridges

Interstate 280 NB over Crystal Springs Off-Ramp

Fair

San Mateo County, California · 04-SM-280-R20.04-SBR · Structure no. 35 0196R

Built
1967
58 years old
Condition
Fair
inspected July 2023
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
250 ft
3 main spans
Daily traffic
49,500
2009 count
Owner
State
State Highway Agency

About this bridge

Interstate 280 NB over Crystal Springs Off-Ramp is a concrete continuous box beam or girders - multiple carrying Interstate 280 NB over Crystal Springs Off-Ramp 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 49,500 vehicles a day, projected to reach 66,974 by 2040. The structure is 250 ft (76.3 m) long and 70 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesInterstate 280 NB
CrossesCrystal Springs Off-Ramp
Location04-SM-280-R20.04-SBR
RouteInterstate 280
Coordinates37.61448, -122.4242
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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating96.5 US tons
Inventory rating57.9 US tons

Structure

MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length250 ft (76.3 m)
Longest span114 ft (34.8 m)
Deck width70 ft (21.2 m)
Roadway width66 ft (20.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic49,500 (2009)
Projected traffic66,974 by 2040
Trucks0%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
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 Interstate 280 NB over Crystal Springs Off-Ramp built?

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

What condition is Interstate 280 NB over Crystal Springs Off-Ramp 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 Interstate 280 NB over Crystal Springs Off-Ramp carry?

About 49,500 vehicles per day (2009 count).

How long is Interstate 280 NB over Crystal Springs Off-Ramp?

The structure is 250 ft (76.3 m) long with a longest span of 114 ft (34.8 m) and a deck 70 ft wide.

Who owns Interstate 280 NB over Crystal Springs Off-Ramp?

It is owned by the State Highway Agency.