Greenwich Reservoir Dam Reservoir Report
Last Updated: December 5, 2025
Greenwich Reservoir Dam in Ohio, completed in 1921, serves as a vital structure for both recreation and water resource management.
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Summary
Owned by the local government and regulated by the Department of Natural Resources, this earth dam stands at a height of 19.9 feet and has a storage capacity of 79 acre-feet. The dam, located in Greenwich, Huron County, Ohio, on a tributary to the Southwest Branch Vermilion River, covers a surface area of 8.5 acres and has a drainage area of 1.4 square miles.
Despite its historical significance and recreational value, Greenwich Reservoir Dam is facing challenges. Classified with a high hazard potential and poor condition assessment as of its last inspection in October 2016, the dam requires regular monitoring and potential maintenance to ensure its safety and functionality. With a maximum discharge capacity of 1106 cubic feet per second, the dam's critical role in flood control and water supply underscores the importance of addressing its maintenance needs promptly.
As a central feature in the local landscape and water infrastructure, Greenwich Reservoir Dam represents a crucial link between water resource management and recreational activities. Its historical legacy and current condition highlight the importance of ongoing maintenance and risk management to ensure the safety and functionality of this essential structure for the community and the environment.
Year Completed |
1921 |
Dam Length |
700 |
Dam Height |
19.9 |
River Or Stream |
TRIBUTARY TO SOUTHWEST BRANCH VERMILION RIVER |
Primary Dam Type |
Earth |
Surface Area |
8.5 |
Drainage Area |
1.4 |
Nid Storage |
79 |
Hazard Potential |
High |
Nid Height |
20 |
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.
Greenwich Reservoir Dam