Tremont Mill Pond Reservoir Report
Nearby: Route 25 #1 Dam Rose Brook Lower Dam
Last Updated: December 20, 2025
Tremont Mill Pond, also known as Tremont Iron Works, is a historic site located in Wareham, Massachusetts.
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Summary
Built in 1845, this earth dam stands at 15 feet high and spans a length of 1200 feet, creating a reservoir with a storage capacity of 340 acre-feet. The pond serves multiple purposes including hydroelectric power generation, fire protection, irrigation, and recreation.
Managed by the Federal Energy Regulatory Commission, Tremont Mill Pond has a spillway width of 24 feet and a maximum discharge capacity of 1555 cubic feet per second. Despite its high hazard potential, the condition assessment of the dam is currently not available. The reservoir covers an area of 57 acres and has a drainage area of 53 square miles, providing vital water resources for the surrounding area.
With a very high risk rating and a lack of updated emergency action plans, there is a need for increased monitoring and risk management measures at Tremont Mill Pond. As a significant water resource in Plymouth County, Massachusetts, this site holds historical and environmental importance for the region. Climate and water resource enthusiasts will find Tremont Mill Pond to be a unique blend of history, hydroelectric power, and recreational opportunities set against the backdrop of the Weweantic River.
Year Completed |
1845 |
Dam Length |
1200 |
Dam Height |
15 |
River Or Stream |
Weweantic River |
Primary Dam Type |
Earth |
Surface Area |
57 |
Drainage Area |
53 |
Nid Storage |
340 |
Outlet Gates |
Slide (sluice gate) - 2 |
Hazard Potential |
High |
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.
Tremont Mill Pond