Is Your Well Water Safe?

About 15% of Americans get their drinking water from private wells. Is this water safe?

The American Academy of Pediatrics recommends testing well water at least once a year. Private wells are not regulated by government agencies. The owners of the wells are responsible for the safety of their water. Sometimes the water might be okay for adults, but children’s smaller size makes them more vulnerable to the health effects of contaminated water. 


The EPA reports that 23% of wells tested have levels of contaminants that are high enough to be a risk to human health. The most common contaminants were radon, trace elements like arsenic and uranium, nitrate, and fluoride. These include naturally-occurring contaminants as well as chemicals found in fertilizers. 

Substances like gasoline, insecticides, and disinfectants were found in 60% of wells tested, but not in concentrations high enough to threaten health. Bacteria like E. coli were found in about one third of the wells, with signs of fecal contamination found in 34%.

About half of the wells had levels of contaminants high enough to make the water taste bad, even if the level was not high enough to be dangerous.

The Ozark Plateaus aquifer system

Homes in Northwest Arkansas using wells are supplied by the Ozark Plateaus aquifer system. The EPA did not find any wells showing levels of contamination high enough to threaten adult human health in our aquifer.

While this is good news, it does not mean that you shouldn’t be cautious about your well water when it comes to your children. For example, an infant under six months who drinks water contaminated with nitrate above the health cutoff may die. The cutoff point is 10 milligrams per liter. While no wells in Northwest Arkansas containing 10 milligrams per liter were found, there were several containing 1-10 milligrams. 

And while no wells in Northwest Arkansas showed dangerous levels of any one contaminant, some did show groups of contaminants — up to six — in single wells. 

The dangers of contaminated water

An article in the latest issue of Pediatrics, the Journal of the American Academy of Pediatrics, lists a wide range of effects that can be caused by common groundwater contaminants. These range from increased risk of cancer to developmental problems, gastrointestinal effects, and specific diseases. 

In many cases, the contaminants in private wells are natural to the local area. However, it is also possible to have fecal contamination of water from farm animals or a faulty septic system. Flooding can carry contaminants into wells. Fracking and earthquakes can cause contamination. Sometimes the construction of a well can be an issue. “The 2 most common threats to the health of private well users are poor well construction and a lack of well owner knowledge,” say the authors of the study.

Well water should be tested regularly, with extra testing if there is damage to the well or if family members have unexplained illnesses. 

The article also recommends that parents ask about the source of water at schools and childcare facilities.