US Bridges

U.S. Highway 101 over Franklin Av & Nwp RR

Fair

Marin County, California · 04-MRN-101-R20.89-NVTO · Structure no. 27 0090L

Built
1974
51 years old, rebuilt 2012
Condition
Fair
inspected June 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete Continuous
Length
395 ft
4 main spans
Daily traffic
61,500
2009 count
Owner
State
State Highway Agency

About this bridge

U.S. Highway 101 over Franklin Av & Nwp RR is a prestressed concrete continuous box beam or girders - multiple carrying U.S. Highway 101 over Franklin Av & Nwp RR in Marin County, California. It was built in 1974 and reconstructed in 2012, so it is 51 years old, younger 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 61,500 vehicles a day, roughly 5% of them trucks, projected to reach 77,824 by 2045. The structure is 395 ft (120.4 m) long and 78 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesU.S. Highway 101
CrossesFranklin Av & Nwp RR
Location04-MRN-101-R20.89-NVTO
RouteU.S. Route 101
CountyMarin County
StateCalifornia
Coordinates38.10191, -122.56171
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionJune 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 alignment8: Equal to present desirable criteria
Operating rating46.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHL 93
Structure length395 ft (120.4 m)
Longest span112 ft (34.1 m)
Deck width78 ft (23.7 m)
Roadway width75 ft (22.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic61,500 (2009)
Projected traffic77,824 by 2045
Trucks5%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad
Detour if closed1.9 mi (3 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 U.S. Highway 101 over Franklin Av & Nwp RR built?

It was built in 1974, making it 51 years old in 2025. It was reconstructed in 2012.

What condition is U.S. Highway 101 over Franklin Av & Nwp RR 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 June 2023.

How much traffic does U.S. Highway 101 over Franklin Av & Nwp RR carry?

About 61,500 vehicles per day (2009 count), of which roughly 5% are trucks.

How long is U.S. Highway 101 over Franklin Av & Nwp RR?

The structure is 395 ft (120.4 m) long with a longest span of 112 ft (34.1 m) and a deck 78 ft wide.

Who owns U.S. Highway 101 over Franklin Av & Nwp RR?

It is owned by the State Highway Agency.