The lake level is now around 11.0′ on the Sunapee Harbor gauge. This is “at the high end” of the operating range (8.0′ to 11.0′) defined by the New Hampshire Department of Environmental Services, according to June Fichter, the executive director of the Lake Sunapee Protective Association.
“A great amount of water is now flowing through the dam,” said Fichter. “There is little that can be done when soils are saturated, snow and ice is melting and rains continue. Likewise, at times of low water level, by law, NH-DES must allow a certain flow through the dam to maintain minimum flows in the river.”
Looking at long-term averages for this time of year, with average precipitation, melt and saturation conditions, the Sunapee lake level is generally 10.2’ to 10.4’ on the harbor gauge. This is 7 to 9.5 inches lower than present level. Higher levels than the present have also been seen.
“The control of flow or allowable flow through the dam is more complicated than lake level alone. There are minimum flows established for the Sugar River, based primarily on required volumes needed for assimilation of sewage treatment plant releases, and there are maximum levels based on potential flood damage downstream,” added Fichter.
A measurement of 10.5′ on the gauge, which corresponds to an elevation of 1,093.15′ above sea level, is considered the “full lake” or the desired lake level from June 1 though summer.