Before having your water tested, ask local experts such as Extension specialists, water treatment plant officials, or state and local health and environmental agencies for advice about which tests should be done on your water. When testing, make sure you follow the sampling techniques given by the lab. In a bacteria-contaminated water system, chlorination of the well is commonly recommended as a solution. Another option is filtering or treating the water at the tap. Otherwise, to fully correct the water supply, the source of contamination must be removed or the water must come from a new well that is not affected by the contaminated source or that taps a deeper aquifer.
Wells do stop supplying water, either because they go dry or due to other factors.
In some instances, what happens is that the water table drops below the pump intake level or the intake screen at the end of the pump becomes clogged. Once the problem is corrected or the ground water level rises, the wells are back in action. Drought or seasonal declines in the water level most commonly affect shallow wells. Increased pumping will also lower the water level. High rates of pumping for industrial, municipal, or agricultural purposes can drop the water table below existing wells.