Old Redwood HWY over Willow Brook Creek
PoorSonoma County, California · 0.5 MI N/O US 101 · Structure no. 20C0516
- Built
- 1999
- 26 years old
- Condition
- Poor
- inspected June 2023
- Type
- Box Beam or Girders - Multiple
- Prestressed Concrete Continuous
- Length
- 165 ft
- 3 main spans
- Daily traffic
- 19,980
- 2013 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
Old Redwood HWY over Willow Brook Creek is a prestressed concrete continuous box beam or girders - multiple carrying Old Redwood HWY over Willow Brook Creek in Sonoma County, California. It was built in 1999, so it is 26 years old, younger 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 19,980 vehicles a day, roughly 3% of them trucks, projected to reach 26,991 by 2045. The structure is 165 ft (50.3 m) long and 85 ft wide. If it were closed, the detour would be 5.6 mi (9 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 | 7 Good | Some minor problems. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Old Redwood HWY over Willow Brook Creek built?
It was built in 1999, making it 26 years old in 2025.
What condition is Old Redwood HWY over Willow Brook 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 2023.
How much traffic does Old Redwood HWY over Willow Brook Creek carry?
About 19,980 vehicles per day (2013 count), of which roughly 3% are trucks.
How long is Old Redwood HWY over Willow Brook Creek?
The structure is 165 ft (50.3 m) long with a longest span of 63 ft (19.2 m) and a deck 85 ft wide.
Who owns Old Redwood HWY over Willow Brook Creek?
It is owned by the City or Municipal Highway Agency.