Pratts Pond Dam Reservoir Report
Nearby: Hayes Pond Dam Windle Pond Dam
Last Updated: December 15, 2025
Pratts Pond Dam, located in Grafton, Massachusetts, is a private dam regulated by the Department of Conservation and Recreation.
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Summary
The dam, situated on Big Bummet Brook, serves primarily for recreational purposes and stands at a height of 11.7 feet with a hydraulic height of 9.3 feet. With a storage capacity of 30.3 acre-feet, the dam has a surface area of 3.7 acres and a drainage area of 4.7 acres.
Despite being classified with a high hazard potential, the condition assessment of Pratts Pond Dam is considered fair as of the last inspection in May 2016. The dam has a moderate risk assessment rating of 3 and an inspection frequency of every 2 years. While the dam does not have outlet gates or associated structures listed, it has an uncontrolled spillway type with a width of 0 feet. The emergency action plan for the dam was last revised in March 2014.
Water resource and climate enthusiasts will find Pratts Pond Dam to be an intriguing structure within the New England District, given its private ownership and state regulation. The dam, with its earth design and buttress core type, provides important recreational opportunities while also posing significant risks due to its high hazard potential. With its location on Big Bummet Brook, Pratts Pond Dam serves as both a picturesque landscape feature and a vital piece of infrastructure that requires regular inspection and maintenance to ensure public safety and environmental protection.
Dam Length |
139 |
Dam Height |
11.7 |
River Or Stream |
BIG BUMMET BROOK |
Primary Dam Type |
Earth |
Surface Area |
3.7 |
Hydraulic Height |
9.3 |
Drainage Area |
4.7 |
Nid Storage |
30.3 |
Hazard Potential |
High |
Foundations |
Unlisted/Unknown |
Nid Height |
12 |
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.
Pratts Pond Dam
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