Assunpink #4 Dam

Assunpink Creek· Monmouth, New Jersey· Earth· 24 ft tall

High Hazard Flood Risk Reduction Fish And Wildlife Pond Recreation State Government

Key Takeaway

Assunpink #4 Dam is classified as high hazard in New Jersey. Its primary use is flood risk reduction. 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	24 ft (taller than 83.4% in NJ)
Dam Length	2,900 ft
Dam Type	Earth
Max Storage	4.3K acre-ft
Normal Storage	1.2K acre-ft

Surface Area	225 acres
Drainage Area	6 sq mi
Max Discharge	503 cfs
NID ID	NJ00322

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: June 21, 2022

State Regulated: Yes

Regulatory Agency: NJDEP

Ownership

Division of Fish & Wildlife

State Government

Nearby Dams

Assunpink #5 Dam

Monmouth, NJ

Low Hazard 13 ft

Etra Mill Dam

Mercer, NJ

Low Hazard 11 ft

Assunpink #19 Dam

Monmouth, NJ

Significant Hazard 36 ft

Peddie Lake Dam

Mercer, NJ

High Hazard 15 ft

Imlaystown Lake Dam

Monmouth, NJ

Significant Hazard 20 ft

New Jersey No Name # 82 Dam

Monmouth, NJ

Low Hazard 10 ft

Assunpink #18 Dam

Monmouth, NJ

High Hazard 38 ft

Matrix Detention Basin

Mercer, NJ

Low Hazard 8 ft

Frequently Asked Questions

What is the hazard classification of Assunpink #4 Dam?

Assunpink #4 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 Assunpink #4 Dam?

Assunpink #4 Dam is owned by Division of Fish & Wildlife (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

What is the primary purpose of Assunpink #4 Dam?

Assunpink #4 Dam serves the following purposes: Flood Risk Reduction, Fish And Wildlife Pond, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Assunpink #4 Dam?

Assunpink #4 Dam has a dam height of 24 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 Assunpink #4 Dam last inspected?

Assunpink #4 Dam was last inspected on June 21, 2022. 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.