If you rely ona private wellfor drinking water, testing it regularly is one of the most important things you can do to protect your family’s health. Unlike public water systems that have to meet federal water quality rules, private wellsare not regulated under the Safe Drinking Water Act, meaning it's up to you to ensure your water is safe.
TheEnvironmental Protection Agency and theCenters for Disease Control and Prevention recommend testing well water at least once a year, typically in spring. More frequent testing might be wise if you live near farmlands, industrial sites or landfills –-- or if someone in your home is pregnant or immunocompromised.
You should also test your well if the water’staste, smell or color changes, after flooding or repairs, or following reports of local contamination.
Contaminants vary by region
Since contaminants vary by region, it’s a good idea to check local water quality reports, also known asConsumer Confidence Reports. Contaminants in private wells often mirror those found in nearby small water systems. Check EWG’sTap Water Database to get an idea of potential risks in your area. If nearby communities struggle with waterpollution, chances are your well could be at risk too. Areas nearfarmlands,airports, factories, mines orlandfills, are more prone to contamination.
Stay informed through local news, talk to neighbors and consult county health departments to learn what to watch for in your area and water issues they may have.
The EPA regulatesabout 90 contaminants in public drinking water, but private well owners must conduct tests themselves to ensure their own water safety.
Here are sixcommonly detected contaminants in drinking water to watch for:
Disinfection byproducts. These form when chlorine or chloramine treat water. Linked to cancer and fetal harm, exposure comes from drinking, cooking and bathing.
Nitrates. These come from fertilizer runoff, especially dangerous for infants. Test during pregnancy and a baby’s first six months, ideally after heavy rain in spring or summer.
Heavy metals. Arsenic andchromium-6, both carcinogens, leach from natural deposits and industrial pollution.
PFAS. These toxic“forever chemicals” pollute the water of more than143 million people and are linked to immune issues and cancer.
Radiological contaminants. Radium and uranium from natural deposits or mining. Even low levels may increase cancer risk and pregnancy complications.
Volatile organic compounds, or VOCs. Chemicals liketrichloroethylene, orTCE, tied to cancer and birth defects.
How to test your well water
Everyone deservesaccess to safe, clean drinking water – it’s a basic human right. Yet for the millions of people who rely on private wells, ensuring their water is safe falls entirely on their shoulders.
Unlike those served by public water systems, private wells don’t have regular testing or oversight, leaving them vulnerable to hidden contaminants. Tests for the full range of potential pollutants – like the six common contaminants that threaten drinking water – can be shockingly expensive, often costing hundreds or even thousands of dollars.
This puts comprehensive tests out of reach for many families, even though the responsibility shouldn’t fall to them in the first place. No one should have to choose between their health and the cost of water quality tests.
If you are able to invest in testing, there are three main options. The choice you make will depend on your budget and how thorough you want the results to be.
1. Home test kits
Basic home test kits, available online and at hardware stores, are an affordable and easy way to check for common water issues like bacteria, nitrates, pH, hardness and iron. However, they don’t detect contaminants like PFAS, heavy metals or VOCs.
2. Mail-in lab kits
For more thorough tests, mail-in kits allow you to collect a water sample and send it to a certified lab for detailed analysis. These tests detect a wider range of contaminants, including heavy metals, PFAS and industrial chemicals.
But even the most comprehensive test kits may not cover all the major contaminants of concern. Even the most expensive option only covers some disinfection byproducts, does not test for PFAS and measures total chromium only, not the more hazardous hexavalent form. To avoid costly surprises, make sure you understand what each kit covers before purchasing.
Before purchasing a test, check your local utility’s water quality report. Even though you’re on well water, nearby public water systems can give you a sense of what contaminants are common in your area. This can help you decide which chemicals are most important to test for, so you don’t spend thousands of dollars on multiple tests.
While mail-in lab kits are more expensive –- ranging from $195 to $1,000, depending on the scope – they provide accurate, lab-certified results.
3. State-certified labs
If you have specific concerns, such as proximity to industrial sites or a need for test results for real estate transactions, contact astate-certified lab for professional analysis.
Some counties offerfree or discounted tests, so check with your local authorities first. State-certified labs offer detailed, accurate tests and can customize them according to local risks. You may need professional help for sample collection.
What to do if tests detect contaminants
If your well water contains harmful pollutants, installinga water filter is often the simplest solution.
Carbon filters are effective at removing VOCs and disinfection byproducts.Reverse osmosis systems can remove contaminants like nitrates, PFAS and heavy metals. Treatment of more serious contamination may requirewhole-house filters or UV treatment for bacteria.
EWG’s Tap Water Database can tell you about contaminants found in testing of public water supplies nearby, and provide advice on the best filters for getting them out of drinking water.
EWG's Guide to Safer Drinking Water
Reduce your exposures to common drinking water pollutants with EWG's handy tipsheet!
Take action to stay safe
Individual well owners shouldn’t be responsible for ensuring their drinking water is safe. It’s a public health failure that private well testing is left entirely to homeowners, many of whom can’t afford the expensive test kits needed to detect hazardous chemicals. Reliance on individual well owners to identify dangerous contaminants is unrealistic and leaves millions at risk.
But until stronger, systemic regulations are in place, regularly testing well water is one of the most important steps you can take to safeguard your family’s health.
These tests, combined with proper treatment and an awareness of local risks, help reduce your exposure to harmful pollutants. For region-specific guidance, consider reaching out to local experts, such as your state’s environmental or health department.