You May Be Drinking from a Poisoned Well

Millions of Americans drink well water that contains arsenic, radon, pesticides, and other toxic chemicals.

March 31, 2009

All's not well: Homes that rely on well water may be exposed to toxins, according to a government report.

RODALE NEWS, EMMAUS, PA—A United States Geological Survey (USGS) report released Friday found that 20 percent of household wells sampled across the country contain at least one contaminant at levels of potential health concern. Nitrates and pesticides used in agriculture and on lawns, radon, arsenic, bacteria and viruses, and volatile organic compounds were among the 219 properties and contaminants tested for and found during the study.


THE DETAILS: Researchers sampled 2,100 wells in 48 states from 1991 to 2004. Samples from the Midwest cornbelt and California’s Central Valley often contained levels of nitrates that exceeded federal safe drinking-water standards because of intense chemical fertilizer use. Other manmade contaminants, including herbicides, insecticides, solvents, by-products of disinfectants, and gasoline chemicals were detected at lower concentrations. Testing for bacteria found that more than 30 percent of the 400 wells tested for this type of contamination contained E. coli bacteria.

WHAT IT MEANS: About 43 million people—that’s 15 percent of the U.S population—rely on private well water. If you’re one of those people, don’t panic. But do test your water regularly, says Cliff Treyens, public awareness director for the National Ground Water Association. “Even if it tastes good, there are things you can’t see, taste, or smell in your water that could be harmful.”

Take these steps to ensure safer well water:

• Test often. Have your well water tested once a year for bacteria, nitrates, and contaminants of local concern, or right away if you notice a change in your water’s color, odor, or taste. Call your local or state public health officials to find out what contaminants are relevant to your area. If you live near chemical farmers, you’ll want to make sure your test includes nitrate and pesticide readings. If you live in an area where radon is a concern, test for that. Keep in mind that land once used for chemical-based farming can retain contaminants for years after the farming stops.

Other reasons to test include a broken well cap, or contamination on your or your neighbor’s property. If someone in your household is suffering from recurrent gastrointestinal sickness, have a test done right away to make sure your water’s up to snuff.

• Test with the best. Lesley Desimone, hydrologist with the USGS, suggests people look for certified testing laboratories through their state’s environmental protection or health agency. The Environmental Protection Agency links to a list of these state agencies from their site. Look for companies that are certified to test water quality for public water systems.

• Fix it right. The good news is you can fix the problems outlined in the USGS report. There’s just no one-size-fits all answer. If you still need clarification on your test results, contact the testing lab or call state or local water officials. If contaminants were found, you can contact a water-well-system contractor or water treatment service provider to talk about options. If you live in an area with high radon levels, the Safe Drinking Water Hotline at 800-426-4791 will help you find out how to make sure your drinking water is safe.

• Seek certification. Independent product-testing groups like National Testing Labs and the Water Quality Association certify some water-treatment devices that are in high demand, but not all of them. If a treatment or filtration system you’re considering is not certified, ask questions the seller for product specifications, and make sure they match the your needs. Also ask about maintenance requirements and operating costs.

• Keep your sewage system safe. Nitrates often come from farm fields, but if you have a faulty septic system, it could be contaminating your well with nitrates and bacteria, too. Do regular checks to make sure your sewage situation is in order to protect your groundwater.

• Keep contaminants out. Some naturally occurring contaminants like radon and arsenic cannot be avoided. But industry, homeowners, and farmers can make sound decisions to keep other contaminants out of groundwater in the first place. Support sustainable farmers who don’t use pesticides, chemical fertilizers, or excess raw manure that can end up in ground water. And trade in a turf yard for one lush with native plants that don’t require chemical intervention to stay beautiful. Those plants will also help absorb rainwater better, sending it on its way to an aquifer so you can enjoy it again some day.

For more information about well placement, testing, and ground water treatment, visit