Longs Lake Dam

TRIB PANTHER CREEK· Cass, Illinois· Built 1960· Earth· 28 ft tall
Low Hazard Recreation Water Supply Private

Key Takeaway

Longs Lake Dam is classified as low hazard in Illinois. It was completed in 1960 and is 66 years old. Its primary use is recreation.

Physical Details

Dam Height 28 ft (taller than 54.6% in IL)
Dam Length175 ft
Dam TypeEarth
Max Storage170 acre-ft
Normal Storage85 acre-ft
Year Completed1960 (66 years old)
NID IDIL00505

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
Last Inspection: June 6, 2019
State Regulated: Yes
Regulatory Agency: IDNR

Ownership

MRS. ORLAND LYNN, C/O EDWARD LONG

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Longs Lake Dam?

Longs Lake 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 Longs Lake Dam?

Longs Lake Dam is owned by MRS. ORLAND LYNN, C/O EDWARD LONG (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Longs Lake Dam built?

Longs Lake Dam was completed in 1960, making it 66 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 Longs Lake Dam?

Longs Lake Dam serves the following purposes: Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Longs Lake Dam?

Longs Lake Dam has a dam height of 28 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 Longs Lake Dam last inspected?

Longs 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.