Spencer Lake
Key Takeaway
Spencer Lake is classified as high hazard in California. It was completed in 1876 and is 150 years old. Its primary use is flood risk reduction. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.
Physical Details
| Dam Height | 87 ft (taller than 78.3% in CA) |
| Dam Length | 400 ft |
| Dam Type | Earth |
| Max Storage | 73 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 0 sq mi |
| Year Completed | 1876 (150 years old) |
| NID ID | CA00673 |
Safety Information
Loss of human life is likely if the dam fails.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Town of Hillsborough
Local Government
Nearby Dams
Crocker
San Mateo, CA
High Hazard 45 ftSan Andreas
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High Hazard 107 ftLower Crystal Springs
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High Hazard 149 ftPilarcitos
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High Hazard 103 ftLaurel Creek
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High Hazard 40 ftCanada Road
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Low Hazard 52 ftMarina Lagoon
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Low Hazard 17 ftNotre Dame
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High Hazard 51 ftFrequently Asked Questions
What is the hazard classification of Spencer Lake?
Spencer Lake is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Spencer Lake?
Spencer Lake is owned by Town of Hillsborough (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Spencer Lake built?
Spencer Lake was completed in 1876, making it 150 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 Spencer Lake?
Spencer Lake serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Spencer Lake?
Spencer Lake has a dam height of 87 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 Spencer Lake last inspected?
Spencer Lake was last inspected on June 23, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.