Bon Tempe

Lagunitas Creek· Marin, California· Built 1949· Earth· 98 ft tall
High Hazard Other Water Supply Public Utility

Key Takeaway

Bon Tempe is classified as high hazard in California. It was completed in 1949 and is 77 years old. Its primary use is other. 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 98 ft (taller than 81.7% in CA)
Dam Length1,150 ft
Dam TypeEarth
Max Storage4.3K acre-ft
Surface Area140 acres
Drainage Area3 sq mi
Year Completed1949 (77 years old)
NID IDCA00207

Safety Information

High Hazard

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?

Emergency Action Plan: Yes
Last Inspection: September 15, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Marin Municipal Water District

Public Utility

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Bon Tempe?

Bon Tempe 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 Bon Tempe?

Bon Tempe is owned by Marin Municipal Water District (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Bon Tempe built?

Bon Tempe was completed in 1949, making it 77 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 Bon Tempe?

Bon Tempe serves the following purposes: Other, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Bon Tempe?

Bon Tempe has a dam height of 98 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 Bon Tempe last inspected?

Bon Tempe was last inspected on September 15, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.