Great Notch Reservoir Dam Reservoir Report

Last Updated: December 10, 2025

The Great Notch Reservoir Dam, located in West Paterson, New Jersey, is a vital structure owned by the local government and regulated by the NJDEP.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1898, this Earth-type dam stands at 74 feet tall and spans 460 feet in length, serving primarily for water supply purposes. With a storage capacity of 640 acre-feet and a normal storage of 537 acre-feet, the dam plays a crucial role in managing the water resources in the region.

Sitting on the Yantecaw Brook, the Great Notch Reservoir Dam has a high hazard potential but has been assessed as satisfactory in terms of condition. The dam's last inspection in June 2021 revealed its structural integrity, and emergency preparedness measures are in place. Although the dam has not undergone significant modifications over the years, its operation and maintenance are crucial for ensuring the safety and security of the surrounding community in the event of any unforeseen emergencies.

With its rich history dating back over a century, the Great Notch Reservoir Dam remains a key component of New Jersey's water infrastructure. As climate change continues to impact water resources, the proper management and maintenance of dams like Great Notch are essential for safeguarding the region's water supply and adapting to changing environmental conditions.

Year Completed

1898

Dam Length

460

Dam Height

74

River Or Stream

Yantecaw Brook

Primary Dam Type

Earth

Surface Area

33

Drainage Area

0.3

Nid Storage

640

Hazard Potential

High

Nid Height

74
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.