Henderson Lake Dam Reservoir Report

Last Updated: December 16, 2025

Henderson Lake Dam, located in Tahawus, New York, is a privately-owned earth dam completed in 1900 for recreational purposes.


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Summary

With a height of 19 feet and a length of 283 feet, the dam has a storage capacity of 3,468 acre-feet and serves as a key feature for water-based activities in the area. The dam is situated on Indian Brook and is regulated by the New York State Department of Environmental Conservation (NYS DEC), ensuring that it meets stringent permitting, inspection, and enforcement standards.

Despite being classified as having a low hazard potential, the dam is considered to have a moderate risk level, indicating the need for ongoing monitoring and risk management measures. The spillway of the dam is uncontrolled with a width of 30 feet, allowing for excess water to flow out safely. The surrounding area has a surface area of 306 acres and a drainage area of 17 square miles, further highlighting the importance of the dam in managing water resources and maintaining recreational opportunities for the local community.

With its picturesque location in Essex County, New York, Henderson Lake Dam stands as a vital structure for both water resource management and recreational enjoyment. As a focal point for outdoor activities such as fishing, boating, and hiking, the dam plays a crucial role in providing a safe and sustainable environment for visitors to appreciate the beauty of nature while ensuring the protection of downstream areas from potential flooding risks.

Year Completed

1900

Dam Length

283

Dam Height

19

River Or Stream

INDIAN BROOK

Primary Dam Type

Earth

Surface Area

306

Drainage Area

17

Nid Storage

3468

Hazard Potential

Low

Nid Height

19
       
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.