A home using a well for its water source obtains the water via drilling to access groundwater in underground aquifers. The well water is usually drawn to the surface by a submersible pump wells can vary greatly in depth, water volume and water quality. Well water typically contains more minerals in solution than surface water and may require treatment to soften the water by removing minerals such as calcium, magnesium, arsenic, iron and manganese. Calcium and magnesium causes what is known as hard water, which can precipitate and clog pipes or burn out water heaters. Iron and manganese can appear as dark flecks that stain clothing and plumbing, and can promote the growth of iron and manganese bacteria that can form slimy black colonies that clog pipes.
Shallow pumping wells can often supply drinking water at a very low cost, but because impurities from the surface easily reach shallow sources, a greater risk of contamination occurs for these wells when they are compared to deeper wells.
The quality of the well water can be significantly increased by lining the well, sealing the well head, ensuring the area is kept clean and free from stagnant water and animals, moving sources of contamination (latrines, garbage pits) and carrying out hygiene education. It is important that the well is cleaned with 1% chlorine solution after construction and periodically every 6 months.
Outbreaks of waterborne disease in the U.S. are mostly associated with private or communal water wells, or other non-community water systems. Most of the bacteria, viruses, parasites, and fungi that contaminate well water comes from humans and other animal fecal material. Common bacterial contaminants include E. coli, Salmonella, Shigella, and Campylobacter jejuni. Common viral contaminants include norovirus, sapovirus, rotavirus, enteroviruses, and hepatitis A and E. Parasites include Giardia lamblia, Cryptosporidium, Cyclospora, and microsporidia. Chemical contamination is a common problem with groundwater. Nitrates from sewage or fertilizer are a particular problem for children. Pesticides and volatile organic compounds, from many sources are the most commonly occurring pollutant chemicals in the U.S., and may be identifiable in more than a third of all U.S. wells, although this is mostly at levels below U.S. water standards. Some chemicals are commonly present in water wells at levels that are not toxic, but which can cause other problems.
Upon the construction of a new test well, it is considered best practice to invest in a series of chemical and biological tests on the well water in question.
Many consumers do not know they can obtain the results of an annual comprehensive water test performed by their municipal water supplier at no charge! Just go to www.epa.gov/safewater/ccr/whereyoulive.html?OpenView#map.
For those of us responsible for our own water supply, it is important to conduct a comprehensive well water test.