Contra Loma

SAN JOAQ RIVER OS· Contra Costa, California· Built 1967· Earth· 82 ft tall
High Hazard Water Supply Federal Government

Key Takeaway

Contra Loma is classified as high hazard in California. It was completed in 1967 and is 59 years old. Its primary use is water supply. 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 82 ft (taller than 77.1% in CA)
Dam Length1,050 ft
Dam TypeEarth
Max Storage2.6K acre-ft
Normal Storage2.1K acre-ft
Surface Area81 acres
Drainage Area1 sq mi
Max Discharge838 cfs
Year Completed1967 (59 years old)
Year Modified2001
NID IDCA10143

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: August 17, 2020
State Regulated: No

Ownership

RECLAMATION

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Contra Loma?

Contra Loma 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 Contra Loma?

Contra Loma is owned by RECLAMATION (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Contra Loma built?

Contra Loma was completed in 1967, making it 59 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 Contra Loma?

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

How tall is Contra Loma?

Contra Loma has a dam height of 82 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 Contra Loma last inspected?

Contra Loma was last inspected on August 17, 2020. 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.