Private Well Water: Using Data to Increase Well Testing and Treatment
Nearly half of New Hampshire residents get their water supply from unregulated private wells, many of which have contaminants at levels that exceed state and federal health-based limits. Some of these contaminants, such as arsenic and radon, have been linked to cancer and other negative health outcomes.
To provide a better picture of which areas of the state may be at higher risk for well water contamination, and to encourage private well users to test their water, the New Hampshire Environmental Public Health Tracking (EPHT) Program has summarized private well water quality data for the most commonly occurring contaminants, both naturally occurring and from human sources. This work is funded by the US Centers for Disease Control and Prevention (CDC).
EPHT worked collaboratively with the New Hampshire Public Health Lab and NHDES to access and combine private well water quality data from more than 23,000 wells from 2006 to 2020, and to make the data available through interactive maps, graphs, and tables in a Private Well Water Quality Dashboard.
The Dashboard is now available through the NH DHHS Data Portal. It allows users to choose from 14 common contaminants and view multiple water quality statistics, such as the percentage of wells tested over a drinking water standard or median concentration of contaminants in well water in the area of interest. These water quality measures can be used to understand well water quality trends observed in tested private wells in and around the town or county of interest. The Dashboard also displays survey data regarding well testing practices and estimates of populations served by private wells in each county.