Green Haven Correctional Facility Dam Reservoir Report

Last Updated: December 5, 2025

The Green Haven Correctional Facility Dam, also known as the Prison Reservoir Dam, is a concrete structure located in Poughquag, New York.


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Summary

Completed in 1939, this dam serves multiple purposes including fire protection and providing a small fish pond. With a height of 40 feet and a length of 176 feet, the dam has a storage capacity of 322 acre-feet and a drainage area of 4.45 square miles.

Despite its historical significance, the Green Haven Correctional Facility Dam is classified as having a high hazard potential and a poor condition assessment. The dam is regulated by the New York State Department of Environmental Conservation (NYS DEC) and undergoes regular inspections, with the last one conducted in November 2020. The dam's spillway is uncontrolled with a width of 100 feet, and it has a maximum discharge capacity of 3,324 cubic feet per second.

Given its moderate risk level and the need for maintenance, the Green Haven Correctional Facility Dam presents an opportunity for water resource and climate enthusiasts to advocate for improved risk management measures and potential rehabilitation efforts. With its location in Dutchess County and proximity to Gardner Hollow Brook, the dam's maintenance and safety are crucial for protecting local communities and ecosystems.

Year Completed

1939

Dam Length

176

Dam Height

40

River Or Stream

GARDNER HOLLOW BROOK

Primary Dam Type

Concrete

Surface Area

23

Drainage Area

4.45

Nid Storage

322

Hazard Potential

High

Nid Height

40
       
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.