Shay Lake Dam Reservoir Report

Last Updated: December 13, 2025

Shay Lake Dam, located in Sandyston Township, New Jersey, is a state-regulated earth dam primarily used for recreation.


°F

°F

mph

Wind

%

Humidity

Summary

With a height of 24 feet and a length of 475 feet, the dam offers a surface area of 8 acres and a drainage area of 0.7 square miles. The dam has a low hazard potential and was last inspected in July 2005, with a satisfactory condition assessment at that time.

Managed by the New Jersey Department of Environmental Protection (NJDEP), Shay Lake Dam provides a storage capacity of 64 acre-feet and a maximum discharge rate of 70 cubic feet per second. The dam is situated on the Flat Brook-TR river and falls under the jurisdiction of Congressional District 05, represented by Josh S. Gottheimer. Despite its age, the dam's condition remains satisfactory, ensuring the safety and recreational enjoyment of the surrounding area.

Water resource and climate enthusiasts will appreciate Shay Lake Dam for its role in providing recreational opportunities while maintaining a low hazard potential. With a history of state regulation and inspection, the dam continues to meet guidelines and ensure public safety. As a key feature in Sussex County, New Jersey, Shay Lake Dam stands as a testament to responsible water management and environmental stewardship in the region.

Dam Length

475

Dam Height

24

River Or Stream

Flat Brook-TR

Primary Dam Type

Earth

Surface Area

8

Drainage Area

0.7

Nid Storage

64

Hazard Potential

Low

Nid Height

24
       
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.