State Route 1 over Blue Slide Gulch
FairMendocino County, California · 01-MEN-001-75.00 · Structure no. 10 0166
- Built
- 1946
- 79 years old, rebuilt 1989
- Condition
- Fair
- inspected September 2023
- Type
- Slab
- Concrete Continuous
- Length
- 143 ft
- 5 main spans
- Daily traffic
- 830
- 2009 count
- Owner
- State
- State Highway Agency
About this bridge
State Route 1 over Blue Slide Gulch is a concrete continuous slab carrying State Route 1 over Blue Slide Gulch in Mendocino County, California. It was built in 1946 and reconstructed in 1989, so it is 79 years old, older 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 830 vehicles a day, roughly 3% of them trucks, projected to reach 2,142 by 2043. The structure is 143 ft (43.6 m) long and 32 ft wide. If it were closed, the detour would be 67.7 mi (109 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was State Route 1 over Blue Slide Gulch built?
It was built in 1946, making it 79 years old in 2025. It was reconstructed in 1989.
What condition is State Route 1 over Blue Slide Gulch 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 September 2023.
How much traffic does State Route 1 over Blue Slide Gulch carry?
About 830 vehicles per day (2009 count), of which roughly 3% are trucks.
How long is State Route 1 over Blue Slide Gulch?
The structure is 143 ft (43.6 m) long with a longest span of 28 ft (8.5 m) and a deck 32 ft wide.
Who owns State Route 1 over Blue Slide Gulch?
It is owned by the State Highway Agency.