Mason ST over Arroyo Grande Creek
FairSan Luis Obispo County, California · 0.1 MI S of SR 227 · Structure no. 49C0201
- Built
- 1926
- 99 years old
- Condition
- Fair
- inspected March 2023
- Type
- Arch - Deck
- Concrete
- Length
- 168 ft
- 1 main span
- Daily traffic
- 5,546
- 2010 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
Mason ST over Arroyo Grande Creek is a concrete arch - deck carrying Mason ST over Arroyo Grande Creek in San Luis Obispo County, California. It was built in 1926, so it is 99 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 6 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 5,546 vehicles a day, roughly 3% of them trucks, projected to reach 5,111 by 2045. The structure is 168 ft (51.2 m) long and 31 ft wide. If it were closed, the detour would be 1.2 mi (2 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Mason ST over Arroyo Grande Creek built?
It was built in 1926, making it 99 years old in 2025.
What condition is Mason ST over Arroyo Grande Creek 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 March 2023.
How much traffic does Mason ST over Arroyo Grande Creek carry?
About 5,546 vehicles per day (2010 count), of which roughly 3% are trucks.
How long is Mason ST over Arroyo Grande Creek?
The structure is 168 ft (51.2 m) long with a longest span of 120 ft (36.6 m) and a deck 31 ft wide.
Who owns Mason ST over Arroyo Grande Creek?
It is owned by the City or Municipal Highway Agency.