Swamp Locks Reservoir Report
Last Updated: December 17, 2025
Swamp Locks, also known as Upper Pawtucket Canal Dam, is a private hydroelectric structure located in Lowell, Massachusetts.
°F
°F
mph
Wind
%
Humidity
Summary
Built in 1823, this concrete gravity dam stands at a height of 15 feet and has a length of 105 feet. With a storage capacity of 4500 acre-feet and a surface area of 720 acres, the dam serves multiple purposes including fire protection, flood risk reduction, and recreation.
Managed by the Federal Energy Regulatory Commission, Swamp Locks has a controlled spillway with a width of 80 feet. Despite its low hazard potential, the dam is considered to have a very high risk due to its age and lack of condition assessment. The last inspection in May 2019 revealed that the condition assessment was not available, highlighting the need for further evaluation and potential risk management measures.
Although Swamp Locks does not have associated locks, it is one of 15 structures in the area that contribute to the operation and function of the dam. As climate and water resource enthusiasts explore the historical and ecological significance of this dam, its location within the Upper Pawtucket Canal and its role in the local ecosystem provide valuable insights into the intersection of human infrastructure and natural water systems in the region.
Year Completed |
1823 |
Dam Length |
105 |
Dam Height |
15 |
River Or Stream |
Upper Pawtucket Canal |
Primary Dam Type |
Concrete |
Surface Area |
720 |
Hydraulic Height |
15 |
Nid Storage |
4500 |
Structural Height |
15 |
Hazard Potential |
Low |
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.
Swamp Locks
Billerica Street 5-65, Lowell