Structure 35 0217 · San Mateo County, CA

Interstate 280 over I 380 & S280-e380 Cnnctr

Carries Interstate 280 over I 380 & S280-e380 Cnnctr, 04-sm-280-r20.97-sbr.

Overall conditionFair

Set by its lowest-rated component: Deck and Superstructure at 5 of 9.

How ratings work
Decksets the rating5/9 · Fair
Superstructuresets the rating5/9 · Fair
Substructure7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT346 FT OVERALL50 FT0ELEVATION · LENGTHS TO SCALE
Deck 5/9 · sets the ratingSuperstructure 5/9 · sets the ratingSubstructure 7/9

346 ft end to end, longest span 151 ft: about 5 semi-trucks nose to tail. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a box-beam bridge.

Built197155 years old
Length346.5 ft105.6 m
Daily traffic101,000counted 2009
Last inspectedJuly 2023every 24 months

Location

StateCalifornia
CountySan Mateo
Location04-sm-280-r20.97-sbr
CarriesInterstate 280
CrossesI 380 & S280-e380 Cnnctr
Coordinates37.62701, -122.43027

Physical Characteristics

MaterialPrestressed Concrete Continuous
DesignBox Beam - Multiple
Total Length346.5 ft (105.6 m)
Max Span150.9 ft (46 m)
Deck Width133.2 ft (40.6 m)
Deck Area4287.4 sq m
Main Spans3
Year Built1971

Traffic

Avg Daily Traffic101,000 (2009)
Truck Traffic2%
Lanes On Bridge8
Lanes Under Bridge4

Inspection & Ownership

Last InspectionJuly 2023
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure Number35 0217

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges