Little Rocky Run Lake Dam

LITTLE ROCKY RUN CREEK· Hancock, Illinois· Built 1971· Earth· 64 ft tall
Significant Hazard Flood Risk Reduction Other Local Government

Key Takeaway

Little Rocky Run Lake Dam is classified as significant hazard in Illinois. It was completed in 1971 and is 55 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 64 ft (taller than 96.2% in IL)
Dam Length586 ft
Dam TypeEarth
Max Storage5.2K acre-ft
Normal Storage1.6K acre-ft
Year Completed1971 (55 years old)
NID IDIL00110

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: July 27, 2015
State Regulated: Yes
Regulatory Agency: IDNR

Ownership

HUNT-LIMA DRAINAGE DISTRICT

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Little Rocky Run Lake Dam?

Little Rocky Run 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 Little Rocky Run Lake Dam?

Little Rocky Run Lake Dam is owned by HUNT-LIMA DRAINAGE DISTRICT (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Little Rocky Run Lake Dam built?

Little Rocky Run Lake Dam was completed in 1971, making it 55 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 Little Rocky Run Lake Dam?

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

How tall is Little Rocky Run Lake Dam?

Little Rocky Run Lake Dam has a dam height of 64 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 Little Rocky Run Lake Dam last inspected?

Little Rocky Run Lake Dam was last inspected on July 27, 2015. 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.