Monomonac Dam, Whitney Pond Dam and Red Dam are classified as high hazard.
Table 24: Dams – Winchendon
Lake Monomonac Dam
High Hazard
Winchendon
Public
Whitney Pond Dam
High Hazard
Public
Winchendon
Red Dam
High Hazard
Public
Winchendon
Beaman Pond Dam
Low Hazard
Public
Winchendon
Flis Pond Dam
N/A
Private
Winchendon
Merrill Pond Dam
N/A
Private
Winchendon
Norsky Dam
N/A
Private
Winchendon
Town Pumping Station Dam
N/A
Public
Winchendon
Brow’s Pond Dam
N/A
Public
Winchendon
Hunts Pond Dam
Significant Hazard
Private
Winchendon
Stoddard Pond Dam
Significant Hazard
Private
Winchendon
Tannery Pond Dam
Significant Hazard
Private
*N/A – Information not available as the dam is non-jurisdictional.
Risk Assessment
Based on the hazards identified in this plan and the assessment of risks by the Town of Winchendon, the town considers itself to be at a high risk for Heavy Rain, Snow Melt, Beavers, Nor’easters, Severe Thunderstorms, Heavy Snow, Ice Storms, Blizzard, Wildland Fire; moderate risk Dam Failure, Ice Jams, High Winds, Hurricanes, Tornados, Major Urban Fires, Drought, Extreme Temperatures; low risk for Earthquakes, and landslides. This information is documented in the Winchendon Natural Hazard Matrix and is shown on the Winchendon Local Assessment Map (Appendix 2) as determined at the first meeting of the Winchendon Local Hazard Mitigation Team held on August 14, 2012.
Source: Montachusett Hazard Mitigation Plan P. 21 adopted by Winchendon Board of Selectmen 2016
Phase I
This is the Engineering Phase. This will cost approximately $300,000. It includes designs, permitting, public hearings, and organizing of the project components.
Definitions
High Hazard
Refers to dams located where failure will likely cause loss of life and serious damage to home(s), industrial or commercial facilities, important public utilities, main highway(s) or railroad(s)
Significant Hazard
Refers to dams located where failure may cause loss of life and damage home(s), industrial or commercial facilities, secondary highway(s) or railroad(s) or cause interruption of use or service of relatively important facilities
Low Hazard
Refers to dams located where failure may cause minimal property damage to others. Loss of life is not expected
Source: MA Department of Conservation and Recreation Office of Dam Safety
High hazard dams must be inspected every two years, significant hazard every five years, and low Hazards dams every 10 years. Owners of dams are responsible for having their dam inspected. MGL Chapter 253 and 302 CMR 10.00 requires that dam owners prepare, maintain and update Emergency Action Plans for all High Hazard Potential dams and certain Significant Hazard Potential dams.
Non-jurisdictional dams are not regulated by the Office of Dam Safety or under their jurisdiction. Typically these dams are under 6 feet in height and/or under 15 acre-feet in storage and do not have assigned 'Hazard Code'. Dams owned and regulated by the Federal Government are also typically non-jurisdictional but DO have an assigned Hazard Code.
There are 290 Dams in the Montachusett Region. Forty-five (45) are considered high hazard, 76 are of significant hazards and 54 are of low hazard.
Source: Montachusett Hazard Mitigation Plan P. 21 adopted by Winchendon Board of Selectmen 2016
The Town operates three (3) of the four (4) "High Hazard Dams. There is added insurance and continued maintenance costs ($7,000 each Inspection) for this "High Hazard Dam". White's Mill Pond Dam is the third in a series of "High Hazard Dams". Lake Monomonoc is the largest and first of these "High Hazard Dams" and the Red Dam is the second "High Hazard Dam". A failure at Lake Monomonoc will not save the residents or the Mill. It is five times the size of White's Mill Pond and the capacity of the Pond has been limited by the silt and sediment that has formed over the years. There is a siphon in the Main Dam and over the years when drawn down, that extra silt and sediment has been sent downstream into White's Mill Pond. There are no fish, few Turtles, and the Beavers dig trenches through the muck to move around. There is and has been only one Board in the dam since acquisition. There may be two to three feet of water in the Pond. The meadow is growing. The loss of the Pond is inevitable without intervention. The breach will allow for at least the amount of water there is during 4 months of the year, before the drawdown and neighbors downstream from the dam will have flow constantly.
Open Spaces. There are seven miles of the Millers River in Town and nearly all of it in private hands. At present, Residents must go to Rindge to access Lake Monomonoc and pay. We wanted White's Mill Pond to be open to the public for recreation. That is not possible under current conditions. It is not safe for human consumption of fish or water.