Black Hawk Lake Dam

Wall Lake Outlet· Sac, Iowa· Built 1916· Earth· 12 ft tall
Significant Hazard Flood Risk Reduction Other Recreation State Government

Key Takeaway

Black Hawk Lake Dam is classified as significant hazard in Iowa. It was completed in 1916 and is 110 years old. Its primary use is flood risk reduction. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 12 ft (taller than 3.1% in IA)
Dam Length0 ft
Dam TypeEarth
Max Storage10.5K acre-ft
Normal Storage5.5K acre-ft
Surface Area920 acres
Drainage Area23 sq mi
Max Discharge0 cfs
Year Completed1916 (110 years old)
NID IDIA03524

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: June 6, 2019
State Regulated: Yes
Regulatory Agency: IOWA DNR

Ownership

Iowa Department of Natural Resources

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Black Hawk Lake Dam?

Black Hawk 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 Black Hawk Lake Dam?

Black Hawk Lake Dam is owned by Iowa Department of Natural Resources (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Black Hawk Lake Dam built?

Black Hawk Lake Dam was completed in 1916, making it 110 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 Black Hawk Lake Dam?

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

How tall is Black Hawk Lake Dam?

Black Hawk Lake Dam has a dam height of 12 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 Black Hawk Lake Dam last inspected?

Black Hawk Lake Dam was last inspected on June 6, 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.