Middle Reservoir Dike Reservoir Report

Last Updated: December 19, 2025

Middle Reservoir Dike, located in Medford, Massachusetts, is a crucial structure for water supply purposes in the area.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1891, this earth dam stands at a height of 15 feet and has a hydraulic height of 14 feet, providing a storage capacity of 2720 acre-feet. The reservoir covers a surface area of 52 acres and is a tributary of the Mystic River, regulated by the Department of Conservation and Recreation in Massachusetts.

With a significant hazard potential and assessed as in fair condition, Middle Reservoir Dike is inspected every 5 years to ensure its structural integrity and safety. The dam lacks a spillway and outlet gates, highlighting the importance of regular maintenance and monitoring. Despite its age, the dam continues to play a vital role in the region's water resource management, serving as a key component of the local government's infrastructure.

Managed by the New England District, Middle Reservoir Dike remains a critical asset for the community, with a high risk assessment due to its age and design. The dam's history and role in water supply underscore the importance of ongoing risk management measures and emergency preparedness to safeguard against potential failures and ensure the continued reliability of this essential water resource infrastructure.

Year Completed

1891

Dam Length

340

Dam Height

15

River Or Stream

TRIBUTARY OF MYSTIC RIVER

Primary Dam Type

Earth

Surface Area

52

Hydraulic Height

14

Drainage Area

0.3

Nid Storage

2720

Hazard Potential

Significant

Foundations

Unlisted/Unknown

Nid Height

15
       
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.