U.S. Highway 101 over Hillside
GoodMarin County, California · 04-MRN-101-1.09-SAUS · Structure no. 27 0063R
- Built
- 1954
- 71 years old
- Condition
- Good
- inspected May 2024
- Type
- Girder and Floorbeam System
- Concrete Continuous
- Length
- 318 ft
- 7 main spans
- Daily traffic
- 53,000
- 2009 count
- Owner
- State
- State Highway Agency
About this bridge
U.S. Highway 101 over Hillside is a concrete continuous girder and floorbeam system carrying U.S. Highway 101 over Hillside in Marin County, California. It was built in 1954, so it is 71 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 53,000 vehicles a day, roughly 1% of them trucks, projected to reach 72,592 by 2042. The structure is 318 ft (96.9 m) long and 43 ft wide. If it were closed, the detour would be 1.9 mi (3 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was U.S. Highway 101 over Hillside built?
It was built in 1954, making it 71 years old in 2025.
What condition is U.S. Highway 101 over Hillside 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 Hillside carry?
About 53,000 vehicles per day (2009 count), of which roughly 1% are trucks.
How long is U.S. Highway 101 over Hillside?
The structure is 318 ft (96.9 m) long with a longest span of 48 ft (14.6 m) and a deck 43 ft wide.
Who owns U.S. Highway 101 over Hillside?
It is owned by the State Highway Agency.