State Route 4 over San Joaquin River
FairSan Joaquin County, California · 10-SJ-004-14.15 · Structure no. 29 0050
- Built
- 1933
- 92 years old
- Condition
- Fair
- inspected April 2023
- Type
- Movable - Swing
- Steel
- Length
- 302 ft
- 2 main spans
- Daily traffic
- 19,950
- 2009 count
- Owner
- State
- State Highway Agency
About this bridge
State Route 4 over San Joaquin River is a steel movable - swing carrying State Route 4 over San Joaquin River in San Joaquin County, California. It was built in 1933, so it is 92 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 19,950 vehicles a day, roughly 17% of them trucks, projected to reach 20,919 by 2043. The structure is 302 ft (92 m) long and 26 ft wide. If it were closed, the detour would be 13 mi (21 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 | 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 State Route 4 over San Joaquin River built?
It was built in 1933, making it 92 years old in 2025.
What condition is State Route 4 over San Joaquin River 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 April 2023.
How much traffic does State Route 4 over San Joaquin River carry?
About 19,950 vehicles per day (2009 count), of which roughly 17% are trucks.
How long is State Route 4 over San Joaquin River?
The structure is 302 ft (92 m) long with a longest span of 129 ft (39.3 m) and a deck 26 ft wide.
Who owns State Route 4 over San Joaquin River?
It is owned by the State Highway Agency.