North Lake A Dam (Spillway) Reservoir Report
Nearby: North Lake B Dam North Lake C Dam
Last Updated: December 14, 2025
North Lake A Dam (Spillway) is a state-owned structure located in Herkimer, New York, with a primary purpose of navigation.
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Summary
Built in 1850, this earth dam stands at a height of 15 feet and spans a length of 160 feet. It has a NID storage capacity of 2208 acre-feet, with a normal storage capacity of 1473 acre-feet, covering a surface area of 442 acres and draining a 31 square mile area.
This controlled spillway dam on the North Lake Outlet is regulated by the NYS DEC and has a low hazard potential. Despite not having a current condition assessment, it has not been rated for its condition. The last inspection took place in October 1995. With a very high risk assessment rating of 1, the dam presents a potential risk that requires careful monitoring and management measures to ensure the safety of the surrounding community and environment. For water resource and climate enthusiasts, North Lake A Dam serves as a vital structure in the local water management system, highlighting the importance of maintaining and assessing infrastructure for long-term sustainability and safety.
Year Completed |
1850 |
Dam Length |
160 |
Dam Height |
15 |
River Or Stream |
NORTH LAKE OUTLET |
Primary Dam Type |
Earth |
Surface Area |
442 |
Drainage Area |
31 |
Nid Storage |
2208 |
Hazard Potential |
Low |
Nid Height |
15 |
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.
North Lake A Dam (Spillway)