Water Quality

Good water quality has many different dimensions, including being clear (low turbidity), odorless, having low salinity, being neither acidic nor basic (neutral pH), and being well oxygenated. ​ High quality waters have a minimum of toxic chemicals (e.g., oils, pesticides, PFAS, and arsenic) and of pathogens (usually measured by level of an  indicator bacteria--E. coli).

High quality waters support a wide array of ​ native plants, animals, and microorganisms living in and around the lakes. However, as concentrations of (non-toxic) nutrients increase (e.g. of phosphorous, nitrogen, and iron), waters go through an aging process characterized by major growth of plants, algae, and cyanobacteria. This process of transforming from ​ lake to pond, pond to marsh, marsh to meadow, and meadow to dry land​ is called eutrophication. Eutrophication is a natural process that typically takes thousands of years. However, human activity that result in increased concentrations of nutrients in the waters can cause the process to advance rapidly (years or decades).

Freshwater scientists and environmental agencies classify waterbodies into three trophic categories​ oligotrophic (good), mesotrophic (threaten), and eutrophic (poor).

  •  The prototypic oligotrophic lake is a large deep lake with crystal clear waters and a rocky or sandy shoreline. Both microorganism and rooted plant growth are sparse, and the lake can support a coldwater fishery.
  • A eutrophic lake is typically shallow with a soft and mucky bottom. Rooted plant growth is abundant along the shore and out into the lake, and algal blooms are not unusual. Water clarity is not good and the water often has a tea color. If deep enough to thermally stratify (described below), the bottom waters can be devoid of oxygen.
  • Mesotrophic is an intermediate trophic state with characteristics between the other two.( NH Department of Environmental Services ) ​

The focus of Wolfeboro Waters has been upon the issues above in Crescent Lake, Rust Pond, Sargents Pond, Lake Wentworth, and Lake Winnipesaukee. Invasive species (such as milfoil​ , zebra mussels ), endangered species, such as loons and fish populations are the focus of other organizations.

More Information:Individual Water Body Water Quality Summaries:
Determining Water Quality ParametersLake Winnipesaukee
Assessing Water Quality Conditions and TrendsWinter Harbor
Sources of NutrientsLake Wentworth and Crescent Lake
Water Quality Conditions and Trends of Wolfeboro WatersRust Pond
Recent Wolfeboro Waters Water Quality Assessment ActivitiesMirror Lake
Ongoging Water Quality Questions 


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