River RD over Mark West CR Trenton RD
FairSonoma County, California · 4.8 MI West of US 101 · Structure no. 20C0064
- Built
- 1960
- 65 years old
- Condition
- Fair
- inspected October 2024
- Type
- Tee Beam
- Concrete Continuous
- Length
- 498 ft
- 10 main spans
- Daily traffic
- 11,700
- 2015 count
- Owner
- County
- County Highway Agency
About this bridge
River RD over Mark West CR Trenton RD is a concrete continuous tee beam carrying River RD over Mark West CR Trenton RD in Sonoma County, California. It was built in 1960, so it is 65 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 11,700 vehicles a day, roughly 3% of them trucks, projected to reach 12,489 by 2046. The structure is 498 ft (151.9 m) long and 32 ft wide. If it were closed, the detour would be 8.7 mi (14 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 | 8 Very Good | No problems noted. |
| Substructure | 8 Very Good | No problems noted. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was River RD over Mark West CR Trenton RD built?
It was built in 1960, making it 65 years old in 2025.
What condition is River RD over Mark West CR Trenton RD 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 October 2024.
How much traffic does River RD over Mark West CR Trenton RD carry?
About 11,700 vehicles per day (2015 count), of which roughly 3% are trucks.
How long is River RD over Mark West CR Trenton RD?
The structure is 498 ft (151.9 m) long with a longest span of 52 ft (15.8 m) and a deck 32 ft wide.
Who owns River RD over Mark West CR Trenton RD?
It is owned by the County Highway Agency.