Denby Dam

WOUNDED KNEE CREEK· Oglala Lakota, South Dakota· Built 1939· Earth· 27 ft tall
Significant Hazard Recreation Water Supply Tribal Government

Key Takeaway

Denby Dam is classified as significant hazard in South Dakota. It was completed in 1939 and is 87 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 27 ft (taller than 71.8% in SD)
Dam Length540 ft
Dam TypeEarth
Max Storage360 acre-ft
Normal Storage210 acre-ft
Surface Area25 acres
Drainage Area23 sq mi
Max Discharge12,470 cfs
Year Completed1939 (87 years old)
NID IDSD00968

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: April 12, 1978
State Regulated: No
Regulatory Agency: DANR

Ownership

OGLALA SIOUX TRIBE

Tribal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Denby Dam?

Denby 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 Denby Dam?

Denby Dam is owned by OGLALA SIOUX TRIBE (Tribal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Denby Dam built?

Denby Dam was completed in 1939, making it 87 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 Denby Dam?

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

How tall is Denby Dam?

Denby Dam has a dam height of 27 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 Denby Dam last inspected?

Denby Dam was last inspected on April 12, 1978. 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.