Allentown Dam

Doctors Creek· Monmouth, New Jersey· Earth· 18 ft tall

High Hazard Recreation Local Government

Key Takeaway

Allentown Dam is classified as high hazard in New Jersey. Its primary use is recreation. 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	18 ft (taller than 66.3% in NJ)
Dam Length	300 ft
Dam Type	Earth
Normal Storage	341 acre-ft

Surface Area	26 acres
Drainage Area	17 sq mi
Max Discharge	751 cfs
NID ID	NJ00308

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: October 19, 2021

State Regulated: Yes

Regulatory Agency: NJDEP

Ownership

Monmouth County Engineering

Local Government

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New Jersey No Name # 84 Dam

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Imlaystown Lake Dam

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Assunpink #4 Dam

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Frequently Asked Questions

What is the hazard classification of Allentown Dam?

Allentown 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 Allentown Dam?

Allentown Dam is owned by Monmouth County Engineering (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

What is the primary purpose of Allentown Dam?

Allentown 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 Allentown Dam?

Allentown Dam has a dam height of 18 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 Allentown Dam last inspected?

Allentown Dam was last inspected on October 19, 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.