Water Quality Monitoring

Monthly water quality testing and sample collection by WWN volunteers helps us monitor conditions in the lake to identify threats and assess long-term trends. It also forms the foundation for watershed management planning.

Lake Monitoring

Each summer Winnisquam Watershed Network volunteers conduct monthly water quality testing and sample collection at three deep-water stations and two shallower near-shore stations in Lake Winnisquam. Samples are transported to the NH Department of Environmental Services (NHDES) laboratory in Concord where they’re tested for color, chloride, chlorophyll-a, alkalinity, pH, total phosphorus and conductivity.

This program is part of the comprehensive Lake Winnisquam Tiered Monitoring Plan, which the WWN began implementing in 2017. It builds on the database previously established by several neighborhood groups on the lake through two volunteer monitoring programs, the UNH Lakes Lay Monitoring Program (LLMP) and the NHDES Volunteer Lake Assessment Program (VLAP). The comprehensive program allows us to coordinate volunteers, share resources & equipment, and synchronize the sampling to allow for better comparability of the data generated.  See the most recent lake VLAP report.

Tributary Monitoring

In the summer of 2018 the Winnisquam Watershed Network began implementing a tributary monitoring program as recommended by the Lake Winnisquam Tiered Monitoring Plan. Tributary monitoring is conducted monthly throughout the summer months by WWN volunteers using protocols from the NHDES Volunteer Rivers Assessment Program (VRAP). The sampling is conducted at eight stream locations where water flows into Lake Winnisquam, and at one location at the outlet to Silver Lake. The samples are tested for dissolved oxygen, chloride, pH, turbidity, total phosphorus and conductivity.  See the most recent tributary VRAP report.

What are we finding?

In general Lake Winnisquam has excellent water quality, with better than average water clarity and low phosphorus and dissolved organic matter. We do need to remain vigilant however. The near-shore stations have indicated a slight decrease in clarity over time, which we will continue to keep an eye on. The conductivity and chloride levels in our lake are definitely on the rise, most likely from the urbanization of the watershed and in particular the use of road salt on impervious surfaces. This is a trend that’s been seen in freshwater bodies throughout the northeast, but seems to be a bit worse in Winnisquam.  Click here to see the lake water quality reports.