Old Sonoma Road over State Route 29
FairNapa County, California · 04-NAP-029-10.70-NAP · Structure no. 21 0087
- Built
- 1961
- 64 years old
- Condition
- Fair
- inspected April 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 307 ft
- 4 main spans
- Daily traffic
- 7,260
- 1989 count
- Owner
- State
- State Highway Agency
About this bridge
Old Sonoma Road over State Route 29 is a prestressed concrete stringer/multi-beam or girder carrying Old Sonoma Road over State Route 29 in Napa County, California. It was built in 1961, so it is 64 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 7,260 vehicles a day, roughly 3% of them trucks, projected to reach 8,298 by 2041. The structure is 307 ft (93.5 m) long and 43 ft wide. If it were closed, the detour would be 3.1 mi (5 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| 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 Old Sonoma Road over State Route 29 built?
It was built in 1961, making it 64 years old in 2025.
What condition is Old Sonoma Road over State Route 29 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 April 2023.
How much traffic does Old Sonoma Road over State Route 29 carry?
About 7,260 vehicles per day (1989 count), of which roughly 3% are trucks.
How long is Old Sonoma Road over State Route 29?
The structure is 307 ft (93.5 m) long with a longest span of 65 ft (19.8 m) and a deck 43 ft wide.
Who owns Old Sonoma Road over State Route 29?
It is owned by the State Highway Agency.