When a water well goes dry, there are options for solving the problems other than drilling a new well, including reducing water usage, lowering the pump or drilling to deepen the well. Drilling a new well is expensive and should be the last resort.
Water well drillers tap into aquifers, which are beds of rock surrounded by water. The well allows the water to collect in a small reservoir from which the pump removes the water. In a well that is working correctly, more water flows into the pit as the pump removes what is there. As the pump continues, the water level slowly drops due to drawdown creating a cone of depression surrounding the well. When the pump stops, this cone returns to a normal level. With a dry well, the depression becomes so severe the pump is above the water level and stops pumping.
By reducing water usage, the well owner reduces the amount of drawdown and helps to keep the pump submerged. If the problems continue while conserving water, the driller is sometimes able to lower the pump deeper into the water to prevent them, although this often requires a new and more powerful pump. If there is not enough room at the bottom of the well to lower the pump, drillers sometimes are able to drill deeper at less expense than drilling a new well.