Mill Pond Dam Reservoir Report

Last Updated: December 6, 2025

Mill Pond Dam, located in Ancramdale, New York, is a historic masonry dam completed in 1890 for hydroelectric power generation and recreation purposes.


°F

°F

mph

Wind

%

Humidity

Summary

Standing at a height of 10 feet and spanning 40 feet in length, the dam impounds Punch Brook, providing a storage capacity of 6 acre-feet with a maximum discharge of 2788 cubic feet per second. The dam's spillway, of uncontrolled type, is 30 feet wide, contributing to its significant hazard potential.

Managed by a private owner, Mill Pond Dam is regulated by the New York State Department of Environmental Conservation (NYS DEC), with state jurisdiction, permitting, inspection, and enforcement in place. Despite its age, the dam's condition assessment remains unrated, and its emergency action plan was last revised in 2011. The risk assessment for this dam is moderate (3), indicating a level of risk that requires attention and management. With its rich history and continued importance for water resource management and recreation, Mill Pond Dam stands as a significant landmark in Columbia County, New York, deserving of ongoing monitoring and maintenance to ensure public safety and environmental protection.

Year Completed

1890

Dam Length

40

Dam Height

10

River Or Stream

PUNCH BROOK

Primary Dam Type

Masonry

Surface Area

2

Drainage Area

2.6

Nid Storage

6

Hazard Potential

Significant

Nid Height

10
       
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.