Osborn Mills Dam

Passaic River· Somerset, New Jersey· Earth· 15 ft tall
Significant Hazard Water Supply Private

Key Takeaway

Osborn Mills Dam is classified as significant hazard in New Jersey. Its primary use is water supply. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 15 ft (taller than 51.4% in NJ)
Dam Length250 ft
Dam TypeEarth
Max Storage100 acre-ft
Normal Storage30 acre-ft
Surface Area10 acres
Drainage Area10 sq mi
Max Discharge500 cfs
NID IDNJ00365

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 16, 2022
State Regulated: Yes
Regulatory Agency: NJDEP

Ownership

New Jersey-American Water Company

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Osborn Mills Dam?

Osborn Mills 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 Osborn Mills Dam?

Osborn Mills Dam is owned by New Jersey-American Water Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

What is the primary purpose of Osborn Mills Dam?

Osborn Mills 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 Osborn Mills Dam?

Osborn Mills Dam has a dam height of 15 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 Osborn Mills Dam last inspected?

Osborn Mills Dam was last inspected on March 16, 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.