Macopin Reservoir Dam

Pequannock River· Morris, New Jersey· Built 1892· Stone· 34 ft tall
High Hazard Water Supply Local Government

Key Takeaway

Macopin Reservoir Dam is classified as high hazard in New Jersey. It was completed in 1892 and is 134 years old. Its primary use is water supply. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 34 ft (taller than 92.6% in NJ)
Dam Length434 ft
Dam TypeStone
Max Storage206 acre-ft
Normal Storage101 acre-ft
Surface Area12 acres
Drainage Area64 sq mi
Max Discharge17,600 cfs
Year Completed1892 (134 years old)
NID IDNJ00320

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

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

Emergency Action Plan: Yes
Last Inspection: April 14, 2021
State Regulated: Yes
Regulatory Agency: NJDEP

Ownership

City of Newark, Department of Water and Sewer Utilities

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Macopin Reservoir Dam?

Macopin Reservoir Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Macopin Reservoir Dam?

Macopin Reservoir Dam is owned by City of Newark, Department of Water and Sewer Utilities (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Macopin Reservoir Dam built?

Macopin Reservoir Dam was completed in 1892, making it 134 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 Macopin Reservoir Dam?

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

How tall is Macopin Reservoir Dam?

Macopin Reservoir Dam has a dam height of 34 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 Macopin Reservoir Dam last inspected?

Macopin Reservoir Dam was last inspected on April 14, 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.