US Bridges

US Highway 101 SB over UP RR AMTRAK N101-SPRING

Good

San Luis Obispo County, California · 05-SLO-101-55.72-PSRS · Structure no. 49 0149L

Built
1958
67 years old
Condition
Good
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
700 ft
6 main spans
Daily traffic
30,500
2009 count
Owner
State
State Highway Agency

About this bridge

US Highway 101 SB over UP RR AMTRAK N101-SPRING is a steel stringer/multi-beam or girder carrying US Highway 101 SB over UP RR AMTRAK N101-SPRING in San Luis Obispo County, California. It was built in 1958, so it is 67 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 30,500 vehicles a day, roughly 8% of them trucks, projected to reach 38,694 by 2043. The structure is 700 ft (213.4 m) long and 31 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesUS Highway 101 SB
CrossesUP RR AMTRAK N101-SPRING
Location05-SLO-101-55.72-PSRS
RouteU.S. Route 101
Coordinates35.61209, -120.69095
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionOctober 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 geometry3: Basically intolerable, requiring high priority of corrective action
Approach roadway alignment8: Equal to present desirable criteria
Operating rating32.5 US tons
Inventory rating25 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length700 ft (213.4 m)
Longest span132 ft (40.2 m)
Deck width31 ft (9.4 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30,500 (2009)
Projected traffic38,694 by 2043
Trucks8%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and railroad
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 US Highway 101 SB over UP RR AMTRAK N101-SPRING built?

It was built in 1958, making it 67 years old in 2025.

What condition is US Highway 101 SB over UP RR AMTRAK N101-SPRING in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2023.

How much traffic does US Highway 101 SB over UP RR AMTRAK N101-SPRING carry?

About 30,500 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is US Highway 101 SB over UP RR AMTRAK N101-SPRING?

The structure is 700 ft (213.4 m) long with a longest span of 132 ft (40.2 m) and a deck 31 ft wide.

Who owns US Highway 101 SB over UP RR AMTRAK N101-SPRING?

It is owned by the State Highway Agency.