Graham Lake Flood Control Reservoir Report
Nearby: Graham Lake Dam Green Lake
Last Updated: December 20, 2025
Located in Ellsworth, Maine, Graham Lake Flood Control is a crucial hydroelectric structure designed to manage the Union River's water flow.
°F
°F
mph
Wind
%
Humidity
Summary
Completed in 1994, this concrete gravity dam stands at 58 feet tall and stretches 855 feet in length, with a storage capacity of 130,000 acre-feet and a surface area of 10,300 acres. With a maximum discharge rate of 24,000 cubic feet per second, the dam serves multiple purposes, including hydroelectric power generation and recreation.
Managed by the Federal Energy Regulatory Commission, Graham Lake Flood Control plays a significant role in flood control and water resource management in the region. The dam's uncontrolled spillway, with a width of 720 feet, helps regulate water levels during periods of high flow, reducing the risk of flooding downstream. While the dam has a high hazard potential, its risk assessment is moderate, reflecting the ongoing efforts to ensure its safety and effectiveness.
With its strategic location and impressive engineering, Graham Lake Flood Control stands as a testament to effective water resource management and climate resilience. As a key structure in the region, it exemplifies the balance between harnessing natural resources for energy production and safeguarding communities against the potential risks of flooding. Its importance in maintaining the Union River's ecosystem and supporting local recreation activities underscores the critical role it plays in the area's environmental and economic sustainability.
Year Completed |
1994 |
Dam Length |
855 |
Dam Height |
58 |
River Or Stream |
Union River |
Surface Area |
10300 |
Drainage Area |
499 |
Nid Storage |
130000 |
Hazard Potential |
High |
Nid Height |
58 |
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.
Graham Lake Flood Control