A drilled irrigation well consists of a hole bored into the ground, with the upper part being lined with casing. The casing prevents the collapse of the borehole walls and (with a drive shoe or grout seal) prevents surface or subsurface contaminants from entering the water supply. The casing also provides a housing for a pumping mechanism and for the pipe that moves water from the pump to the surface.
The quality of materials used in water well drilling is an important factor. Casing must meet certain specifications since substandard pipe does not have sufficient strength to withstand driving without potential damage to the joints. Such damage may allow shallow or surface water to enter the well.
The casing must also have a drive shoe attached to the bottom to prevent damage during driving and to make a good seal with the formation. In some applications, a grout seal of cement or bentonite may also be recommended to prevent contamination. Below the casing, the lower portion of the borehole is the intake through which water enters the well. The intake may be an open hole in solid bedrock or it may be screened and gravel-packed, depending upon the geologic conditions.
Once the water well is completed, it is pumped to develop the well and determine the yield. Many areas need further work after drilling to remove fine material remaining from the drilling process so that water can more readily enter the well. Possible development methods include compressed air (blowing), bailing, jetting, surging, or pumping. The quantity of water (yield test) is usually measured during development. The minimum test time is one hour.
Water wells can be drilled for many purposes including residential and commercial irrigation, windmills and livestock water sources. Various methods include geothermal drilling, open loop drilling, and closed loop drilling. East Wichita Well & Pump Service also offers water line installation. For more information on water well drilling visit www.wellowner.org, or call us at 316.644.1401.