Rancho Seco

Tr Hadselville Cr· Sacramento, California· Built 1972· Earth· 58 ft tall
High Hazard Tailings Recreation Public Utility

Key Takeaway

Rancho Seco is classified as high hazard in California. It was completed in 1972 and is 54 years old. Its primary use is tailings. 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 58 ft (taller than 66.2% in CA)
Dam Length3,400 ft
Dam TypeEarth
Max Storage3.0K acre-ft
Surface Area165 acres
Drainage Area2 sq mi
Year Completed1972 (54 years old)
NID IDCA00825

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: November 10, 2021
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Sacramento Municipal Utility District

Public Utility

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Rancho Seco?

Rancho Seco 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 Rancho Seco?

Rancho Seco is owned by Sacramento Municipal Utility District (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Rancho Seco built?

Rancho Seco was completed in 1972, making it 54 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 Rancho Seco?

Rancho Seco serves the following purposes: Tailings, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Rancho Seco?

Rancho Seco has a dam height of 58 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 Rancho Seco last inspected?

Rancho Seco was last inspected on November 10, 2021. 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.