Olson Dam

Tongue River-TR· Pembina, North Dakota· Built 1957· Earth· 67 ft tall

High Hazard Flood Risk Reduction Local Government

Key Takeaway

Olson Dam is classified as high hazard in North Dakota. It was completed in 1957 and is 69 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	67 ft (taller than 98% in ND)
Dam Length	990 ft
Dam Type	Earth
Max Storage	1.1K acre-ft
Normal Storage	61 acre-ft

Surface Area	7 acres
Drainage Area	6 sq mi
Year Completed	1957 (69 years old)
NID ID	ND00056

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 3, 2022

State Regulated: Yes

Regulatory Agency: ND DWR

Ownership

Pembina County WRB

Local Government

Nearby Dams

Hanks Corner Dam

Cavalier, ND

Significant Hazard 58 ft

Herzog Dam

Pembina, ND

Significant Hazard 38 ft

Bourbanis Dam

Cavalier, ND

Significant Hazard 73 ft

Senator Young Dam

Cavalier, ND

High Hazard 85 ft

Olga Dam

Cavalier, ND

Low Hazard 65 ft

Goschke Dam

Pembina, ND

Significant Hazard 33 ft

Weiler Dam

Pembina, ND

Significant Hazard 39 ft

Dam ND00973

Pembina, ND

Low Hazard 10 ft

Frequently Asked Questions

What is the hazard classification of Olson Dam?

Olson Dam 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 Olson Dam?

Olson Dam is owned by Pembina County WRB (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Olson Dam built?

Olson Dam was completed in 1957, making it 69 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 Olson Dam?

Olson Dam 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 Olson Dam?

Olson Dam has a dam height of 67 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 Olson Dam last inspected?

Olson Dam was last inspected on November 3, 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.