Grenloch Lake Dam

South Branch Timber Creek· Gloucester, New Jersey· Built 1907· Earth· 21 ft tall
Significant Hazard Recreation Water Supply Local Government

Key Takeaway

Grenloch Lake Dam is classified as significant hazard in New Jersey. It was completed in 1907 and is 119 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 21 ft (taller than 78.3% in NJ)
Dam Length250 ft
Dam TypeEarth
Max Storage272 acre-ft
Normal Storage92 acre-ft
Surface Area21 acres
Drainage Area15 sq mi
Max Discharge0 cfs
Year Completed1907 (119 years old)
NID IDNJ00402

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: March 4, 2022
State Regulated: Yes
Regulatory Agency: NJDEP

Ownership

Township of Washington

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Grenloch Lake Dam?

Grenloch Lake 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 Grenloch Lake Dam?

Grenloch Lake Dam is owned by Township of Washington (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Grenloch Lake Dam built?

Grenloch Lake Dam was completed in 1907, making it 119 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 Grenloch Lake Dam?

Grenloch 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 Grenloch Lake Dam?

Grenloch Lake Dam has a dam height of 21 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 Grenloch Lake Dam last inspected?

Grenloch Lake Dam was last inspected on March 4, 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.