TEX*A*Syst Slide Training Series: Wellhead Management
In rural areas, nearly everyone relies on a private well for drinking water. Most people take for granted that these wells will produce a dependable supply of safe drinking water. However, no federal or state law ensures the quality of drinking water drawn from a private well.
Ground water supplying private wells comes primarily from local precipitation, which seeps through the soil and into underlying sand, gravel, and rock. The water generally travels from areas of high elevation to lower areas, in formations that store and transmit water called “aquifers.”
There are three different types of wells found on rural properties: drilled, driven-point, and hand-dug. Generally, drilled wells with a casing are less susceptible to contamination than driven-point wells or dug wells.
Many structures and activities on farmsteads and at rural homes pose risks to drinking water quality, including wells, petroleum tanks, septic systems, fertilizer and pesticide storage, and livestock wastes.
Because the recharge area that serves a private well may be on the same property as the well or extend onto neighboring properties, the activities of both homeowners and their neighbors directly affect well water quality.
Once contaminated, ground water is usually very difficult and very expensive to clean up. In many cases, it is not possible to restore the water to its previous quality. The only options may be to treat the water, drill a new well, or link up to a public water system.
Most contaminated water is caused by contamination sources too close to the well, improper well construction, inadequate well maintenance, and unused or improperly abandoned wells. Unfortunately, most contaminants can only be detected by testing, and not by taste, smell, or color.
Many contaminants can enter rural water supplies and threaten the health and safety of families. The most common contaminants include microorganisms such as bacteria and viruses, nitrate, and toxic substances such as pesticides, petroleum, and solvents.
Texas requires that new wells be constructed at minimum distances from potential pollution sources. These distances are based, in part, on the natural filtering capacity of the soil to protect the well water.
Increasing the distance between a well and contamination sources may help protect the drinking water for that well, but not ground water as a whole. Any condition that might contaminate ground water should be evaluated and improved, even if the potential source is far from a well.
Credits
Home Page: http://waterhome.brc.tamus.edu