Most water well contractors will probably say they've never had a problem drilling a plumb borehole. And it's probably true. But if you're not testing for plumbness and alignment-and you're installing municipal, industrial, or irrigation wells with lineshaft turbine pumps-you're making a big mistake. "Many contractors don't have the tools to do precise plumbness and alignment tests," says Gary Hix, RG, CWD/PI, the 2019 Groundwater Foundation McEllhiney Lecturer. "They think they know their wells are straight enough, but all you have to do is lose one big well, and you're in big trouble." If you're primarily drilling domestic wells or other small-diameter, shallow wells, it's not likely a small deviation in plumbness or alignment will cause problems. However, on deep wells or wells to be equipped with lineshaft turbine pumps, the plumbness, straightness, and alignment of the well is extremely important to the operation of the pumping equipment. Plumbness is the horizontal deviation of the well centerline from a true vertical centerline. A well can be straight and not plumb. Alignment refers to horizontal deviation between the actual well centerline and a straight line. A well that is not plumb or is misaligned (the casing contains bends or "doglegs") can put excess wear and tear on the pump. "If a lineshaft turbine pump is out of alignment, it will start to vibrate; the bushings will start to wear," Hix says. "Then, once they wear too much, the drive shaft starts to wobble and shake. It wears out the pumping equipment too fast." A sharp bend in the well causes the lineshaft to bend and will eventually cause metal failure and breakage.
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