Old Duncans Grd RD over Austin Creek
PoorSonoma County, California · Btn Czdero Hy&austn CR RD · Structure no. 20C0094
- Built
- 1924
- 101 years old
- Condition
- Poor
- inspected June 2024
- Type
- Truss - Thru
- Steel
- Length
- 265 ft
- 2 main spans
- Daily traffic
- 30
- 2015 count
- Owner
- County
- County Highway Agency
About this bridge
Old Duncans Grd RD over Austin Creek is a steel truss - thru carrying Old Duncans Grd RD over Austin Creek in Sonoma County, California. It was built in 1924, so it is 101 years old, older than the California average of 54.8 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
It carries about 30 vehicles a day, projected to reach 107 by 2046. The structure is 265 ft (80.8 m) long and 18 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 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Superstructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Channel and channel protection | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Old Duncans Grd RD over Austin Creek built?
It was built in 1924, making it 101 years old in 2025.
What condition is Old Duncans Grd RD over Austin Creek in?
The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in June 2024.
How much traffic does Old Duncans Grd RD over Austin Creek carry?
About 30 vehicles per day (2015 count).
How long is Old Duncans Grd RD over Austin Creek?
The structure is 265 ft (80.8 m) long with a longest span of 117 ft (35.7 m) and a deck 18 ft wide.
Who owns Old Duncans Grd RD over Austin Creek?
It is owned by the County Highway Agency.