Water Quality

There are eleven parameters of Little Sunapee water that are routinely monitored by our water quality team, including phosphorus and chloride. High levels of phosphorus can lead to harmful algae blooms and cyanobacteria, sometimes referred to as blue-green algae, which are toxic to humans and pets. For decades our phosphorus levels have been well within the ideal level and half the average for NH lakes. In some years phosphorus in the surface layer has been undetectable by either of the laboratories we use. However, a record number of toxic cyanobacteria blooms have been reported recently in other NH lakes. When this occurs, lakes with these blooms are closed to the public until the threat abates.

Chloride levels in NH lakes are receiving increased attention from DES. The number of NH lakes impaired with chloride is rising, and even in the unimpaired water bodies the state average chloride level is increasing. Some sources of chloride are obvious, such as road salt. Less obvious is the contribution from domestic water treatment systems. Salt used in home water treatment makes its way through septic systems into the lake. 

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