US Bridges

State Route 84 over Caltrain UP RR Shasta ST

Poor

San Mateo County, California · 04-SM-084-24.86-RDWC · Structure no. 35 0052

Built
1965
60 years old
Condition
Poor
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
264 ft
4 main spans
Daily traffic
43,000
2009 count
Owner
State
State Highway Agency

About this bridge

State Route 84 over Caltrain UP RR Shasta ST is a steel stringer/multi-beam or girder carrying State Route 84 over Caltrain UP RR Shasta ST in San Mateo County, California. It was built in 1965, so it is 60 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 43,000 vehicles a day, roughly 3% of them trucks, projected to reach 56,075 by 2046. The structure is 264 ft (80.6 m) long and 94 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesState Route 84
CrossesCaltrain UP RR Shasta ST
Location04-SM-084-24.86-RDWC
RouteState Highway 84
CountySan Mateo County
StateCalifornia
Coordinates37.47889, -122.22044
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating91.1 US tons
Inventory rating54.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length264 ft (80.6 m)
Longest span116 ft (35.4 m)
Deck width94 ft (28.7 m)
Roadway width72 ft (22 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic43,000 (2009)
Projected traffic56,075 by 2046
Trucks3%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway and railroad
Detour if closed3.7 mi (6 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$3.9 million (2024 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was State Route 84 over Caltrain UP RR Shasta ST built?

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

What condition is State Route 84 over Caltrain UP RR Shasta ST in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in May 2024.

How much traffic does State Route 84 over Caltrain UP RR Shasta ST carry?

About 43,000 vehicles per day (2009 count), of which roughly 3% are trucks.

How long is State Route 84 over Caltrain UP RR Shasta ST?

The structure is 264 ft (80.6 m) long with a longest span of 116 ft (35.4 m) and a deck 94 ft wide.

Who owns State Route 84 over Caltrain UP RR Shasta ST?

It is owned by the State Highway Agency.