Mirror Lake Dam

Flat Creek· Adams, North Dakota· Built 1909· Earth· 19 ft tall
Significant Hazard Recreation Local Government

Key Takeaway

Mirror Lake Dam is classified as significant hazard in North Dakota. It was completed in 1909 and is 117 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 19 ft (taller than 63% in ND)
Dam Length800 ft
Dam TypeEarth
Max Storage895 acre-ft
Normal Storage573 acre-ft
Surface Area94 acres
Drainage Area0 sq mi
Year Completed1909 (117 years old)
NID IDND00137

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: August 31, 2022
State Regulated: Yes
Regulatory Agency: ND DWR

Ownership

Hettinger Park Board

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Mirror Lake Dam?

Mirror Lake Dam is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Mirror Lake Dam?

Mirror Lake Dam is owned by Hettinger Park Board (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Mirror Lake Dam built?

Mirror Lake Dam was completed in 1909, making it 117 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 Mirror Lake Dam?

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

How tall is Mirror Lake Dam?

Mirror Lake Dam has a dam height of 19 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 Mirror Lake Dam last inspected?

Mirror Lake Dam was last inspected on August 31, 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.