Lake Cohasset Dam

MILL CREEK· Mahoning, Ohio· Built 1897· Masonry· 25 ft tall
Significant Hazard Recreation Local Government

Key Takeaway

Lake Cohasset Dam is classified as significant hazard in Ohio. It was completed in 1897 and is 129 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 25 ft (taller than 42.1% in OH)
Dam Length190 ft
Dam TypeMasonry
Max Storage373 acre-ft
Normal Storage175 acre-ft
Surface Area28 acres
Drainage Area71 sq mi
Max Discharge6,987 cfs
Year Completed1897 (129 years old)
NID IDOH00417

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: Yes
Last Inspection: October 13, 2021
State Regulated: Yes
Regulatory Agency: Department of Natural Resources

Ownership

Mill Creek Metropolitan Park Dist.

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lake Cohasset Dam?

Lake Cohasset 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 Lake Cohasset Dam?

Lake Cohasset Dam is owned by Mill Creek Metropolitan Park Dist. (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lake Cohasset Dam built?

Lake Cohasset Dam was completed in 1897, making it 129 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 Lake Cohasset Dam?

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

How tall is Lake Cohasset Dam?

Lake Cohasset Dam has a dam height of 25 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 Lake Cohasset Dam last inspected?

Lake Cohasset Dam was last inspected on October 13, 2021. 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.