State Announces Its 2021 Fall Drawdown of Lakes

Concord, NH – The New Hampshire Department of Environmental Services (NHDES) announced today that the annual fall drawdown of the lakes and ponds controlled by dams owned by NHDES will be initiated according to the schedule below.

1. Crystal Lake in Gilmanton drawdown will start at the beginning of October in conjunction with upstream bridge work. Upon completion, the water level will be raised to the usual winter drawdown level.
2. Highland Lake in Stoddard will have a 1-foot drawdown starting on September 7. This is to facilitate work being done downstream at Island Pond Dam. On October 11, the level will be returned to the normal drawdown.  
3. Island Pond drawdown will also begin on September 7 for the purpose of construction on the dam.
4. These larger lakes generally do not reach their full drawdowns until mid or late March. The values listed above are generally the maximum levels reached, although during any given year the levels reached can be either higher or lower due to weather conditions.

The depth of drawdown listed above is not from the current level, but is from the normal full pond level. Due to changing ice and hydrologic conditions, these levels can vary throughout the winter. Since the hydrologic conditions and recreational uses of these water bodies vary, the degree and date of the start of drawdown for each lake vary and could be affected by the amount of rainfall during the period. In addition, the actual date at which the drawdown will begin could vary by a few days based on operational constraints. However, at three dams, the drawdowns will be initiated or accelerated on a specific Saturday in October to provide recreational opportunities for canoeists and kayakers in the rivers below these dams. The schedule for these recreational opportunities is as follows:

• Horace Lake will have a release for recreational use downstream on Saturday, October 16. Water release from the dam will begin at 8 AM and end at 4 PM. Between 300 and 400 cfs will be released for that time period.
• Also there will be a recreational release from Northwood Lake (Little Suncook River) on October 23 starting at 8 AM and end at 4 PM.
• On Saturday, October 30, a release will be made from Greggs Falls Dam in Goffstown to provide an opportunity for canoeing and kayaking in the Piscataquog River downstream. The release will begin at 10 AM.

At the first two of these sites the flow will be reduced to near normal levels by 4 PM that same day. NHDES reminds people that canoeing and kayaking have inherent risks, and paddling the state’s lakes and rivers is at the paddler’s own risk.

Lake drawdowns are conducted each fall to reduce winter ice damage to shoreline properties and to reduce spring flooding.  Drawdowns also give property owners an opportunity to conduct any necessary repairs to their waterfront property, provided they first secure a permit from the NHDES Wetlands Bureau at (603) 271-2147.

Not included in this schedule is Lake Winnipesaukee. Unlike the other lakes in this schedule, Lake Winnipesaukee is not purposely drawn down in the fall. Instead, in the fall after Columbus Day, the releases from Lakeport Dam are reduced from a normal minimum of 250 cubic feet per second (cfs) to a flow between 30 and 50 cfs for a period of up to two weeks to allow for maintenance of the dams and hydropower facilities on the Winnipesaukee River. The flow of 30 to 50 cfs is the minimum flow needed to maintain the downstream aquatic life during this period. This year the reduction will be begun on October 18.

By the middle of the fall, Lake Winnipesaukee is, on average, 15 inches below its springtime full level due to evaporation and releases from the lake that have occurred over the course of the summer.  Because of this summer’s drought, the level of the lake is already at that elevation. When the amount of water released from the dam is reduced after Columbus Day, the lake level is not expected to drop significantly for the remainder of the month of October and, if drought conditions ease in the fall and winter, it is expected to remain relatively stable through the month of December absent any major rainfall events. Depending on the amount of snow on the ground in the winter, the lake level may be lowered further beginning in January to a depth of two feet below the normal full level.

A plot of the average lake levels throughout the year for Lake Winnipesaukee is provided on NHDES’s website at winnipesaukee-graph2021.jpg (2549×1646) (nh.gov). Also included are updated plots of this year’s lake levels, releases from the dam, and precipitation.

The NH Fish and Game Department recommends that if special drawdowns are to be conducted for the purposes of repairing property such as retaining walls or private boat ramps they occur only once in every 5 years. In the event a party may wish to conduct such a drawdown, please contact the NHDES Dam Bureau immediately after receiving all permits required for such work, so that the drawdown can be coordinated with any other work at the same water body being proposed by other parties. In this way the number of special drawdowns can be minimized, and unexpected delays (up to 5 years) for your project can be avoided.