Alderpoint RD over Mcmahon Creek
GoodHumboldt County, California · 14 MI N/O Alderpoint · Structure no. 04C0090
- Built
- 1958
- 67 years old
- Condition
- Good
- inspected February 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 43 ft
- 1 main span
- Daily traffic
- 106
- 2008 count
- Owner
- County
- County Highway Agency
About this bridge
Alderpoint RD over Mcmahon Creek is a prestressed concrete stringer/multi-beam or girder carrying Alderpoint RD over Mcmahon Creek in Humboldt County, California. It was built in 1958, so it is 67 years old, older than the California average of 54.8 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 106 vehicles a day, roughly 5% of them trucks, projected to reach 339 by 2044. The structure is 43 ft (13.1 m) long and 28 ft wide. If it were closed, the detour would be 123.7 mi (199 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| 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 Alderpoint RD over Mcmahon Creek built?
It was built in 1958, making it 67 years old in 2025.
What condition is Alderpoint RD over Mcmahon Creek in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in February 2024.
How much traffic does Alderpoint RD over Mcmahon Creek carry?
About 106 vehicles per day (2008 count), of which roughly 5% are trucks.
How long is Alderpoint RD over Mcmahon Creek?
The structure is 43 ft (13.1 m) long with a longest span of 40 ft (12.2 m) and a deck 28 ft wide.
Who owns Alderpoint RD over Mcmahon Creek?
It is owned by the County Highway Agency.