The total vertical distance from the water surface to the location of the shallow well pump water inlet is referred to as Total Vertical Lift. This distance includes any elevation change from the water source to the pump installation location. One must keep in mind that the water surface, in most cases, fluctuates. This means that allowances also need to be made for the expected range of water surface fluctuation throughout the year. This operating zone limits the situations where a shallow well pump can be recommended.