San Joaquin No. 3 Forebay
Key Takeaway
San Joaquin No. 3 Forebay is classified as low hazard in California. It was completed in 1906 and is 120 years old. Its primary use is hydroelectric.
Physical Details
| Dam Height | 40 ft (taller than 46.3% in CA) |
| Dam Length | 450 ft |
| Dam Type | Earth |
| Max Storage | 20 acre-ft |
| Normal Storage | 19 acre-ft |
| Surface Area | 3 acres |
| Max Discharge | 170 cfs |
| Year Completed | 1906 (120 years old) |
| NID ID | CA00339 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Pacific Gas and Electric Company
Private
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Low Hazard 60 ftFrequently Asked Questions
What is the hazard classification of San Joaquin No. 3 Forebay?
San Joaquin No. 3 Forebay is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates San Joaquin No. 3 Forebay?
San Joaquin No. 3 Forebay is owned by Pacific Gas and Electric Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was San Joaquin No. 3 Forebay built?
San Joaquin No. 3 Forebay was completed in 1906, making it 120 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.
What is the primary purpose of San Joaquin No. 3 Forebay?
San Joaquin No. 3 Forebay serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is San Joaquin No. 3 Forebay?
San Joaquin No. 3 Forebay has a dam height of 40 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.
When was San Joaquin No. 3 Forebay last inspected?
San Joaquin No. 3 Forebay was last inspected on September 8, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.