Big Bend Dam

MISSOURI RIVER· Lyman, South Dakota· Built 1963· Earth·

Key Takeaway

Big Bend Dam is classified as high hazard in South Dakota. It was completed in 1963 and is 63 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 Length10,570 ft
Dam TypeEarth
Max Storage1.9M acre-ft
Normal Storage1.7M acre-ft
Surface Area60,000 acres
Drainage Area5,840 sq mi
Max Discharge390,000 cfs
Year Completed1963 (63 years old)
NID IDSD01092

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: July 24, 2019
State Regulated: No

Ownership

USACE - Omaha District

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Big Bend Dam?

Big Bend 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 Big Bend Dam?

Big Bend Dam is owned by USACE - Omaha District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Big Bend Dam built?

Big Bend Dam was completed in 1963, making it 63 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 Big Bend Dam?

Big Bend Dam serves the following purposes: Flood Risk Reduction, Irrigation, Navigation, Recreation, Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

When was Big Bend Dam last inspected?

Big Bend Dam was last inspected on July 24, 2019. 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.