The average homeowner just assumes that their well is providing them with potable water.
Unfortunately, this misconception is rarely brought to their attention until it is too late and they find out that they have been drinking contaminated water, sometimes for years.
Well systems are mechanical devices and they do break down at times. Poorly maintained or constructed wells can lead to a variety of problems including poor quality water. Certain defects could allow surface water to enter the well and cause contamination, which means that the well is no longer protecting the water supply.
As a responsible well owner, you need to carry out a regular program of well maintenance. Good maintenance means testing your water regularly, disinfecting your well every year, keeping the well area clean and accessible, keeping pollutants as far away from the area as possible and periodically having the mechanics of the well system checked.