Well Pumps

A submersible pump, which is the type most often used in drilled wells, consists of a pump and motor unit. The pump is placed directly into the well, below the water level. Jet pumps are not installed in the well, but installed above ground. Jet pumps operate by forcing water through a jet or Venturi, a narrow, cone-shaped device that creates a partial vacuum (suction) and draws water from the well into the pumping system. Shallow well jet pumps that are used where the water is less than 25 feet below the surface have the jet located in the pump itself. For deeper wells, the jet is located inside the well below the water level. The correct size pump and pump motor depends on the well diameter, the water level in the well, the number of plumbing fixtures, the amount of water use, and the peak water demand. Pumps are rated in gallons per minute (GPM) or gallons per hour (GPH), and pump motors are rated in horsepower (HP). Special water needs - such as for irrigation, heat pumps, or livestock - can increase peak demand and require a pump capable of producing more water. If the required rate of flow to meet the peak demand exceeds the maximum rate at which water can be pumped from the well, the difference can often be made up by increasing the storage capacity of the pressure tank. In some locations, a larger diameter well which is capable of handling a larger pump can provide more water.