Cossayuna Lake Outlet Dam Reservoir Report
Nearby: Carters Pond Dam Joseph Boyd Dam
Last Updated: December 17, 2025
Located in Cossayuna, New York, the Cossayuna Lake Outlet Dam stands as a vital structure for water resource management and recreation.
°F
°F
mph
Wind
%
Humidity
Summary
Completed in 1815, this earthen dam spans 200 feet in length and reaches a height of 10 feet, with a storage capacity of 7908 acre-feet. The dam safeguards the surrounding area by controlling the flow of Whittaker Brook and serving as a controlled spillway during high water events.
Managed by a private entity, the Cossayuna Lake Outlet Dam is regulated by the New York State Department of Environmental Conservation, ensuring its compliance with state permitting, inspection, and enforcement protocols. Despite its low hazard potential, the dam is rated as having a very high risk due to its age and historic significance. While the dam's condition assessment remains unrated, its purpose primarily caters to recreational activities, emphasizing the importance of maintaining its structural integrity for the community's enjoyment and safety.
For water resource and climate enthusiasts, the Cossayuna Lake Outlet Dam offers a glimpse into early engineering practices and their enduring impact on the local landscape. With its quaint setting and historical significance, this dam serves as a reminder of the intricate relationship between human infrastructure, natural water systems, and the need for sustainable management in the face of evolving environmental challenges. As efforts continue to ensure the dam's safety and functionality, it remains a noteworthy site for those interested in the intersection of water resources, infrastructure development, and climate resilience.
Year Completed |
1815 |
Dam Length |
200 |
Dam Height |
10 |
River Or Stream |
WHITTAKER BROOK |
Primary Dam Type |
Earth |
Surface Area |
659 |
Drainage Area |
11.81 |
Nid Storage |
7908 |
Hazard Potential |
Low |
Nid Height |
10 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Dam Data Reference
Condition Assessment
SatisfactoryNo 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
HighDams 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.
Cossayuna Lake Outlet Dam