Concord, NH – The New Hampshire Department of Environmental Services (DES) announced today that the annual fall drawdown of the lakes and ponds controlled by dams operated by DES will be initiated during the next few months according to the schedule below.
The depth of drawdown listed below is not from the current level, but is from the normal full pond level. Since the hydrologic conditions and recreational uses of these water bodies vary, the degree and date of the start of drawdown for each lake is varied 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.
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 DES Wetlands Bureau at (603) 271-2147.
|Angle Pond||Bartlett Brook||Sandown||Oct. 9||2’|
|Ayers Lake||Tributary to Isinglass River||Barrington||Oct. 9||3’|
|Ballard Pond||Taylor Brook||Derry||Oct. 9||2’|
|Barnstead Parade||Suncook River||Barnstead||Sept. 6||10’|
|Basin Brook Dam||Basin Brook||Chatham||Sept. 11|
|Bow Lake||Isinglass River||Strafford||Oct. 9||4’|
|Buck Street||Suncook River||East Pembroke||Oct. 9||6’|
|Bunker Pond||Lamprey River||Epping||Oct. 9||2’|
|Burns Lake||Tributary to Johns River||Whitefield||Oct. 9||1.5’|
|Chesham Pond||Minnewawa Brook||Harrisville||Oct. 9||2’|
|Crystal Lake||Crystal Lake Brook||Enfield||Oct. 9||4’|
|Crystal Lake||Suncook River||Gilmanton||Oct. 9||3’|
|Deering Reservoir||Piscataquog River||Deering||Oct. 1||6’|
|East Washington Pond||Beards Brook||Washington||Oct. 9||2’|
|Glen Lake/Greggs Falls||Piscataquog River||Goffstown||Nov. 1||1’|
|Goose Pond||Goose Pond Brook||Canaan||Oct. 9||7.5’|
|Grafton Pond||Bicknell Brook||Grafton||Oct. 9||2’|
|Great East Lake||Salmon Falls River||Wakefield||Oct. 9||3’|
|Great Pond||Powwow River||Kingston||Oct. 9||1’|
|Highland Lake||North Branch Contoocook River||Stoddard||Oct. 9||3’|
|Horace Lake (aka Weare Reservoir)||Piscataquog River||Weare||Oct. 16||5’|
|Horn Pond||Salmon Falls River||Wakefield||Oct. 1||1.5’|
|Howe Reservoir||Tributary to Minnewawa Brook||Dublin||Oct. 9||6’|
|Island Pond||North Branch Contoocook River||Stoddard||Oct. 9||3’|
|Kezar Lake||Lane River||Sutton||Sept. 30||2’|
|Kilton Pond||Smith River||Grafton||Oct. 9||3’|
|Kingswood Lake||Churchill Brook||Brookfield||Oct. 9||4’|
|Lake Kanasatka||Tributary to Lake Winnipesaukee||Moultonboro||Nov. 1||1.5’|
|Little Sunapee Lake||Kidder Brook||Sunapee||Nov. 1||1’|
|Lovell Lake||Branch River||Wakefield||Oct. 9||3’|
|Mascoma Lake||Mascoma River||Lebanon||Oct. 16||3’|
|Mendums Pond||Little River||Nottingham||Nov. 8||7’|
|Milton Three Ponds||Salmon Falls River||Milton||Oct. 9||4’|
|Newfound Lake||Newfound River||Bristol||Oct. 9||3.5’|
|Nippo Pond||Nippo Brook||Barrington||Oct. 9||2’|
|North River Pond||North River||Nottingham||Oct. 9||1’|
|Northwood Lake||Little Suncook River||Epsom||Oct. 16||6’|
|Opechee Lake||Winnipesaukee River||Laconia||Oct. 10-Oct 23||5’|
|Ossipee Lake||Ossipee River||Effingham||Sept. 6||3’|
|Pawtuckaway Lake||Pawtuckaway River||Nottingham||Oct. 9||7’|
|Pequawket Lake||Tributary to Swift River||Conway||Nov. 1||2’|
|Pine River Pond||Pine River||Wakefield||Oct. 9||8’|
|Pleasant Lake||Tributary to Little Suncook River||Deerfield||Oct. 9||3’|
|Sawyer Lake||Badger Brook||Gilmanton||Oct. 9||3’|
|Shellcamp Pond||Academy Brook||Gilmanton||Oct. 9||2’|
|Silver Lake||Minnewawa Brook||Harrisville||Oct. 9||3’|
|Souhegan Site 10A||Mill Brook||Wilton||Sept. 11|
|Souhegan Site 13||Tributary to Souhegan River||New Ipswich||Sept. 11|
|Souhegan Site 14||Furnace Brook||New Ipswich||Sept. 6|
|Souhegan Site 19||South Branch Souhegan||New Ipswich||Sept. 11|
|Souhegan Site 25B||Temple Brook||Temple||Sept. 11|
|Souhegan Site 26||Blood Brook||Temple||Sept. 11|
|Souhegan Site 28||Tributary to Stony Brook||Lyndeborough||Sept. 11|
|Souhegan Site 35||West Branch Souhegan||New Ipswich||Sept. 11|
|Squam Lake||Squam River||Ashland||Oct. 9||2.5’|
|Sunapee Lake||Sugar River||Sunapee||Oct. 16||3’|
|Suncook Lakes||Suncook River||Barnstead||Oct. 1||5’|
|Sunrise Lake||Dames Brook||Middleton||Oct. 20||2’|
|Sunset Lake||Suncook River||Alton||Oct. 16||7’|
|Trickling Falls||Powwow River||East Kingston||Nov. 1||1’|
|Webster Lake||Chance Brook||Franklin||Oct. 9||2’|
|Winnisquam Lake||Winnipesaukee River||Belmont||Oct. 10-Oct. 23||2’|
Generally, lake levels are allowed to return to the normal full pond level in the spring. However, Angle Pond is allowed to return to normal at the beginning of December, and Chesham Pond is lowered by 4 feet starting Columbus Day for a period of 6 to 8 weeks and the level will be brought up to 2 feet below the normal full pond level for the remainder of winter.
The special drawdowns to be conducted this year include one at Kilton Pond in Danbury, which will be drawn down to 3’ below normal starting on October 9th to accommodate work to be performed on the wooden flashboards on the spillway of the dam. It is estimated that the level will be brought back to the normal water level at the beginning of November after the work is completed. Also, Deering Reservoir will be drawn down to 6’ below normal starting on October 1st to accommodate a major repair to the dam. After the initial phase of construction is complete, the level will be brought back to its normal drawdown level of 4’. In addition, a 10-foot drawdown of Barnstead Parade in Barnstead will be conducted in cooperation with the Barnstead Milfoil Committee. The drawdown will begin on September 6th, and the lake will be lowered in two-foot intervals over a three-week period to enable the BMC to collect data needed to design a treatment program for variable water milfoil that BMC proposes to implement next spring.
Opechee and Winnisquam lakes will be drawdown this year, as they are every even-numbered year, for a period of approximately two weeks in length. Outflows at both lakes will be increased on the 10th of October. The level of Opechee will likely drop rapidly. However, the level in Lake Winnisquam may take a few days to drop because the additional water from the drawdown of Opechee upstream must first pass through it.
In addition to these drawdowns, DES will drain eight of its flood control impoundments in September to perform detailed inspections of the outlet works of the dams. These impoundments include Souhegan Sites 13, 19 and 35 in New Ipswich, Souhegan Site 10A in Wilton, Souhegan Sites 25B and 26 in Temple, Souhegan Site 28 in Lyndeborough and Basin Brook Dam in Chatham. These impoundments will be allowed to refill immediately after the inspections are completed.
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, each year on 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.
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. As a result of the reduction in the amount of water released from the dam after Columbus Day, the lake level does not drop for the remainder of the month of October and is generally maintained at this level through the month of December. 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 is provided on DES’s web site. Also included are updated plots of this year’s lake levels, releases from the dam, and precipitation.