Not counting the electricity it takes to pump it into the house, well water is free. It's not chlorinated or fluoridated, and there are no monthly bills to deal with. Yet, well water may not be as pure as you think, and it may pose risks that could cause illness if not addressed.

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Well water quality depends on many factors, including where a well is located.

Considerations

Determining well water quality takes five factors into consideration: the type of well, the geology of the soil, where the well is located, its age and when the last water tests were done.

Contaminants

Maine Water Testing Labs report that disease-causing bacteria can enter your well water supply through damaged casings or through the walls of a dug or shallow well. Chemicals like arsenic and radon can also contaminate the water from the surrounding rocks, and old pipes can transfer lead into the water.

Maintenance

Take the time to monitor your well water carefully to make sure of consistent quality. Be sure the area around the well is clear and free of animal waste, pay attention to any changes in the taste, smell or color of the water, and get a water test, especially if a household member is pregnant, you've had work done on the well or the well went dry and replenished itself.