Ben Smith Dam Reservoir Report

Last Updated: December 18, 2025

Ben Smith Dam, located in Maynard, Massachusetts, is a privately owned structure on the Assabet River that serves primarily for recreational purposes.


°F

°F

mph

Wind

%

Humidity

Summary

Built in 1870, this gravity-type dam stands at 9 feet high and spans 170 feet in length, with a storage capacity of 760 acre-feet. Despite its age, the dam is in satisfactory condition and has a low hazard potential, making it a relatively safe structure.

The dam is regulated by the Department of Conservation and Recreation in Massachusetts, with state jurisdiction and permitting in place. Regular inspections are conducted, with the last assessment in September 2017 showing satisfactory results. The dam has an uncontrolled spillway and is classified as having a moderate risk level. With its historical significance and continued recreational use, Ben Smith Dam remains a key feature on the Assabet River for water resource and climate enthusiasts to explore and appreciate.

Year Completed

1870

Dam Length

170

Dam Height

9

River Or Stream

ASSABET RIVER

Primary Dam Type

Other

Surface Area

18.5

Hydraulic Height

6

Drainage Area

115

Nid Storage

760

Hazard Potential

Low

Foundations

Unlisted/Unknown

Nid Height

9
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No 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

High
Dams 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.