Mallard Dam

CEDAR CREEK· Lyman, South Dakota· Built 1942· Earth· 20 ft tall

Key Takeaway

Mallard Dam is classified as low hazard in South Dakota. It was completed in 1942 and is 84 years old. Its primary use is fish and wildlife pond.

Physical Details

Dam Height 20 ft (taller than 33.7% in SD)
Dam Length400 ft
Dam TypeEarth
Max Storage166 acre-ft
Normal Storage88 acre-ft
Max Discharge2,080 cfs
Year Completed1942 (84 years old)
NID IDSD02331

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

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

Emergency Action Plan: No
State Regulated: No
Regulatory Agency: DANR

Ownership

USDA FS

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Mallard Dam?

Mallard Dam is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Mallard Dam?

Mallard Dam is owned by USDA FS (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Mallard Dam built?

Mallard Dam was completed in 1942, making it 84 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 Mallard Dam?

Mallard Dam serves the following purposes: Fish And Wildlife Pond, 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.

How tall is Mallard Dam?

Mallard Dam has a dam height of 20 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.

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.