US Bridges

U.S. Highway 101 over Ggt Bellam Andersen

Good

Marin County, California · 04-MRN-101-9.63-SRF · Structure no. 27 0007

Built
1958
67 years old, rebuilt 2003
Condition
Good
inspected May 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
1,024 ft
12 main spans
Daily traffic
172,000
2009 count
Owner
State
State Highway Agency

About this bridge

U.S. Highway 101 over Ggt Bellam Andersen is a concrete continuous box beam or girders - multiple carrying U.S. Highway 101 over Ggt Bellam Andersen in Marin County, California. It was built in 1958 and reconstructed in 2003, 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 172,000 vehicles a day, roughly 2% of them trucks, projected to reach 225,945 by 2042. The structure is 1,024 ft (312.1 m) long and 123 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesU.S. Highway 101
CrossesGgt Bellam Andersen
Location04-MRN-101-9.63-SRF
RouteU.S. Route 101
Coordinates37.95708, -122.50873
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 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 rating74 US tons
Inventory rating44.6 US tons

Structure

MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans12
Design loadHS 20
Structure length1,024 ft (312.1 m)
Longest span108 ft (32.9 m)
Deck width123 ft (37.4 m)
Roadway width117 ft (35.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic172,000 (2009)
Projected traffic225,945 by 2042
Trucks2%
Lanes on structure8
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed3.7 mi (6 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 Ggt Bellam Andersen built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 2003.

What condition is U.S. Highway 101 over Ggt Bellam Andersen 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 May 2024.

How much traffic does U.S. Highway 101 over Ggt Bellam Andersen carry?

About 172,000 vehicles per day (2009 count), of which roughly 2% are trucks.

How long is U.S. Highway 101 over Ggt Bellam Andersen?

The structure is 1,024 ft (312.1 m) long with a longest span of 108 ft (32.9 m) and a deck 123 ft wide.

Who owns U.S. Highway 101 over Ggt Bellam Andersen?

It is owned by the State Highway Agency.