Private drinking water wells can be constructed in three types, which include driven, dug, and drilled wells. No matter the type of private drinking water well, all wells need to be properly constructed, maintained, and inspected. For more information on each well type, read on:
Driven Well
Driven wells are typically easy and inexpensive to install. Normally located in areas with thick sand and gravel, driven wells can measure 30 to 50 feet deep, which is considered relatively shallow. Because driven wells are somewhat shallow, they run the risk of moderate contamination, so driven wells should be covered with a concrete curb and cap about a foot above the ground. Pumps for driven wells are located either on top of the well or in the house, and the land surface around tthe well should allow surface water to run away from the well.
Dug Well
Dug wells are shallower than driven wells, as they are created by shovels and backhoes, and typically only go 10 to 30 feet deep. Dug wells hold a high risk of contimation and can easily go dry when the ground water table drops during a period of drought. Dug wells are often considered dated before drilling equipment was readily available. To minimize risk of contamination, dug wells should be cased with a watertight materials and cement grout or sealent to the top of the well. Much like driven wells, dug wells should be covered by a concrete curb and cap, while the land surface around the well should allow surface water to run away from the well instead of pool around the wellhead.
Drilled Well
Lastly, drilled wells are located about 100 to 400 feet into the bedrock and normally feature submersible pumps located near the bottom of the well. These pumps require special wiring and electrical service. Most drilled wells feature a watertight subsurface connection that helps protect against frost and contamination, while drilled well casing extends into the bedrock to prevent ground water from entering the well. The well casing extends above the ground surface and features a sealant and cap to keep out surface water.
For more information on which type of well is best for your Northern Virginia home, as well as how to properly maintain your well, contact SES. Based in Warrenton, Virginia, SES has been inspecting, servicing, maintaining, and repairing residential and commercial Northern Virginia septic systems since 1987.