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Basic Information about Private Wells

Private wells frequently asked questions:

What is a well?

A well is a hole in the ground used to access groundwater. Click on the links below to learn about the four different types of wells. 
Well water is often used in homes for things like cleaning, cooking, bathing, and drinking.

What is a private well? 

Private wells are not maintained or regulated by the state or county government. 

A well is considered private, or domestic if it is being used by no more than: 
  • Three households or
  • Ten people
If you own a private well, you are responsible for: 
  • Routine well water testing to be sure the water is safe to drink. 
  • Well maintenance and treatment

What is groundwater? 

When rain falls, much of it is absorbed into the ground. Water that is not used by plants moves downward through pores and spaces above the dense rock barrier is called groundwater. Another common term for groundwater is "aquifer" or "groundwater aquifer."

Is the groundwater from a private well safe to drink?

The only way to know for sure if groundwater is safe to drink is to have it tested by an accredited laboratory. Click here to find one in your area

Groundwater can become contaminated and unsafe to drink. Below are some factors that can make water unsafe:
  • Bacteria (fecal) contamination
  • High levels of naturally-occurring contaminants, such as arsenic.
  • Local land-use practices (fertilizers and pesticides)
  • Problems with nearby septic systems
Remember: The well owner is responsible for the safety of the well water. We recommend that well water is tested every year and maintained regularly.

More information

  • Visit the Domestic Well Safety Program website for more information on private wells.
  • For private well-related questions and concerns, contact us.