Many people do not give much thought to their drinking water or where it comes from, only paying mind if the color, taste or pressure is unusual or if warnings are issued in the event of a water main break or flood.
Water for homes and businesses is often sourced from municipal water sources, but private wells also provide water. According to the U.S. Census Housing Survey 2015, 13 million households in the United States rely on private wells to supply their water. Many of these homes are located in hard-to-reach or rural areas where municipal water pipes do not travel.
Public water supplies are typically overseen by a governing body, such as the United States Environmental Protection Agency. However, these organizations may not regulate private wells, nor will they provide recommended criteria or standards for individual wells. As a result, it is up to individuals to make sure their well water is safe for consumption. Private well owners may be surprised to learn that, according to the U.S. Geological Survey, at least 20 percent of private wells contain contaminants, of which 23 percent have levels high enough to be a potential health concern.
Well water is groundwater found in subterranean aquifers. This groundwater comes from rainfall that is absorbed in the soil and slowly seeps downward through the dirt, rock and various underground spaces. Along this path it can pick up contaminants. Common sources of contaminants include farm waste, fertilizers and pesticides, chemical spills, poorly maintained septic systems, and seepage from landfills. Arsenic is also naturally occurring in groundwater, and in some areas the levels are above the EPA threshold for safety.
Unfortunately, many contaminants are undetectable to the eyes, nose and mouth. And unlike public drinking water systems, people with wells typically do not test their water as often as they should. The EPA says that well water should be tested annually for bacteria and nitrates. The environmental medicine experts at Robert Wood Johnson Medical School in New Jersey suggest testing for lead, arsenic, radon, uranium, and other heavy metals every three to five years.
The National Groundwater Association says county health departments can conduct water tests for bacteria and nitrates. Those who want to test for other substances can get a list of state-certified drinking water testing labs. The Well Wise program is administered by the Ontario Ground Water Association and can provide water testing for consumers. This is a good place to start for Canadian residents. Learn more at http://www.ogwa.ca or in the United States at https://water.usgs.gov.