State Route 4 over North Fork Mokelumne Riv
GoodAlpine County, California · 10-ALP-004-12.94 · Structure no. 31 0009
- Built
- 1937
- 88 years old, rebuilt 1986
- Condition
- Good
- inspected October 2023
- Type
- Slab
- Prestressed Concrete
- Length
- 29 ft
- 1 main span
- Daily traffic
- 490
- 2019 count
- Owner
- State
- State Highway Agency
About this bridge
State Route 4 over North Fork Mokelumne Riv is a prestressed concrete slab carrying State Route 4 over North Fork Mokelumne Riv in Alpine County, California. It was built in 1937 and reconstructed in 1986, so it is 88 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 490 vehicles a day, projected to reach 860 by 2045. The structure is 29 ft (8.8 m) long and 32 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 | 1 Imminent Failure | Major deterioration or section loss present in critical structural components. Bridge is closed to traffic but corrective action may put it back in light service. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was State Route 4 over North Fork Mokelumne Riv built?
It was built in 1937, making it 88 years old in 2025. It was reconstructed in 1986.
What condition is State Route 4 over North Fork Mokelumne Riv 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 October 2023.
How much traffic does State Route 4 over North Fork Mokelumne Riv carry?
About 490 vehicles per day (2019 count).
How long is State Route 4 over North Fork Mokelumne Riv?
The structure is 29 ft (8.8 m) long with a longest span of 26 ft (7.9 m) and a deck 32 ft wide.
Who owns State Route 4 over North Fork Mokelumne Riv?
It is owned by the State Highway Agency.