Ponca

WILLOW CREEK· Gregory, South Dakota· Built 1935· Earth·
High Hazard Irrigation Fire Protection Stock Or Small Fish Pond Federal Government

Key Takeaway

Ponca is classified as high hazard in South Dakota. It was completed in 1935 and is 91 years old. Its primary use is irrigation. 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 Length580 ft
Dam TypeEarth
Normal Storage1.2K acre-ft
Year Completed1935 (91 years old)
NID IDSD00545

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 6, 2012
State Regulated: No
Regulatory Agency: DENR

Ownership

BIA

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Ponca?

Ponca 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 Ponca?

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

When was Ponca built?

Ponca was completed in 1935, making it 91 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 Ponca?

Ponca serves the following purposes: Irrigation, Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

When was Ponca last inspected?

Ponca was last inspected on August 6, 2012. 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.