Onderdonk Lake Dam Reservoir Report
Last Updated: December 8, 2025
Located in South Berne, New York, Onderdonk Lake Dam stands as a significant earth dam completed in 1928 with a primary purpose of providing recreational opportunities for visitors.
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Summary
With a height of 11 feet and a length of 100 feet, the dam boasts a storage capacity of 280 acre-feet and a surface area of 64 acres. Situated on the SWITZ KILL river or stream, this dam is regulated by the New York State Department of Environmental Conservation (NYS DEC) and undergoes regular inspections to ensure its structural integrity.
Despite its historical significance, Onderdonk Lake Dam faces challenges in terms of its condition assessment, which has been deemed as poor. With a significant hazard potential and a moderate risk assessment rating, there is a pressing need for effective risk management measures to mitigate any potential emergencies. The dam's spillway type is uncontrolled, with a width of 3 feet, adding to the complexity of its operation and maintenance. With its location in Albany County, New York, and under the jurisdiction of local government ownership, the dam serves as a crucial recreational resource but requires attention to address its current condition and safety concerns.
As a focal point for water resource and climate enthusiasts, Onderdonk Lake Dam symbolizes the intersection of natural beauty and human intervention in managing water resources. With its rich history and ongoing regulatory oversight, the dam presents a case study in balancing the need for recreation with the imperative of ensuring public safety and environmental stewardship. By understanding the complexities of maintaining and managing such critical infrastructure, stakeholders can work towards sustainable solutions that prioritize both community enjoyment and long-term resilience in the face of changing climatic conditions.
Year Completed |
1928 |
Dam Length |
100 |
Dam Height |
11 |
River Or Stream |
SWITZ KILL |
Primary Dam Type |
Earth |
Surface Area |
64 |
Nid Storage |
280 |
Hazard Potential |
Significant |
Nid Height |
11 |
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.
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