Movable Dam At Mays Point Reservoir Report

Last Updated: December 6, 2025

The Movable Dam at Mays Point, also known as the Lock E-25 Dam, is a state-owned structure located in Fox Ridge, Seneca, New York.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1915, this dam plays a critical role in flood risk reduction along the Clyde River, with a primary purpose of ensuring navigation and safety along the waterway. Standing at a height of 10 feet and stretching 165 feet in length, the dam has a storage capacity of 504 acre-feet, serving a drainage area of 864 square miles.

Managed by the New York State Department of Environmental Conservation, the Movable Dam at Mays Point has a controlled spillway with a width of 120 feet, ensuring effective water flow regulation during periods of high discharge. Despite a low hazard potential, the dam is rated for a very high risk due to its age and potential for structural issues. While the condition assessment is currently not rated, regular inspections and state regulatory oversight help to ensure the dam's continued functionality in mitigating flood risks and protecting the surrounding communities. Enthusiasts of water resources and climate management will find the Movable Dam at Mays Point to be a fascinating example of infrastructure designed to balance flood control and navigation needs along a vital waterway in New York.

Year Completed

1915

Dam Length

165

Dam Height

10

River Or Stream

CLYDE RIVER

Primary Dam Type

Other

Drainage Area

864

Nid Storage

504

Hazard Potential

Low

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.