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Groundwater and Groundwater Wells

Ground water is the water that fills cracks and other openings in beds of rocks and sand.  It is a renewable resource that is naturally replenished by precipitation. There are more than 16 million wells in the U.S., tapping ground water for private and public supply, irrigation, livestock, manufacturing, power, and other purposes. About 1/3 of Connecticut's population get their drinking water from ground water.  (Source: National Ground Water Association). Also, since ground water is the baseflow for most rivers, streams and wetlands, its quality is inextricably linked to surface water quality

Sources of Ground Water Contamination, from www.groundwater.org

The majority of people in Woodstock, CT obtain their water from private wells. Ground water quality in Woodstock is generally very good. While the ground is an excellent mechanism for filtering out particulate matter such as leaves, soil, and bugs. However, because Connecticut's major aquifer systems are shallow (typically less than 300 feet deep, with the water table within 50 feet of the land surface) they are susceptible to contamination.  Underground water can get contaminated from industrial, domestic, and agricultural chemicals applied to the ground surface. The most common water quality problem in rural areas is bacterial contamination from septic tanks. Excess nitrogen near agricultural areas can also be a problem. Shallow wells can be more at risk than deeper, drilled wells.

The American Ground Water Trust recommends that all homeowners have their well water tested annually by a certified laboratory. Minimum testing should include coliform bacteria, nitrate and pH (acidity). If the pH is below 7.0, also test for lead, especially in homes built before 1987. If your well is near an operational or abandoned gas station or buried fuel storage, they recommend testing for volatile organic carbons (VOCs). 

The National Ground Water Association suggests you have your well equipment inspected annually by a licensed and/or certified water well contractor. This inspection, along with water testing, will assure your well equipment is sanitary and meets local code requirements.

Steps to Maintain Your Well

  • Keep hazardous chemicals, such as paint, fertilizers, pesticides and motor oil, far away from your well.
  • Maintain a "clean zone" of at least 50 feet between your well and any kennels or livestock operations.
  • Maintain proper separation between your well and waste systems. In Connecticut, the separation must be at least 75 feet.
  • Periodically check the well cover or well cap on top of the casing to ensure it is in good repair and securely attached. The seal should keep out insects and rodents. (If you've ever had a squirrel or chipmunk drown in your well, you will know why this is so important.)
  • Keep your well records in a safe place. These should include annual water well system maintenance and water testing results.
  • Get your water tested anytime there is a change in taste, odor or appearance, or anytime the system is serviced.

More Information and References:

  • For more information or advice on well water testing and treatment, contact the Northeast District Department of Health, 136 Main Street, Killingly, (860) 774-7350 for advice on well water testing and treatment OR the Connecticut DEP Potable Water Program, (860) 434-3705.
  • Connecticut Ground Water Conditions - a two page report by the Ground Water Protection Council.
  • EPA Safe Water - drinking water and health basics, frequently asked questions, etc.
  • The American Ground Water Trust - a non-profit educational organization with information on the hydrologic, economic and environmental significance of groundwater.
  • The National Ground Water Association -  information on ground water and private well water systems.
  • The Groundwwater Foundation - action plans, kids corner, etc.
Conservation Commission
Water, water, everywhere,
Nor any drop to drink.

- Samuel Taylor Coleridge, The Ancient Mariner