Private wells
If your water comes from your own well, none of the public data on this site covers it. Nobody tests a private well unless the owner does.
What to test for
| Test | How often | Why |
|---|---|---|
| Total coliform / E. coli | Every year | Sign of septic or surface contamination |
| Nitrate | Every year | Farm and septic runoff, dangerous for infants |
| Arsenic | Once, then every few years | Natural in rock across much of the country |
| Lead | Once | From well components and household plumbing |
| Uranium, radium, radon | Once | Natural in granite and deep aquifers |
| PFAS | Once, if near a likely source | Firefighting foam, landfills, biosolids, factories |
| Manganese, iron, hardness | Once | Staining, taste, and choosing treatment |
Use a certified lab
Home test strips are fine for hardness and a rough nitrate check, but not for arsenic, lead or PFAS at the levels that matter. Use a lab certified by your state, or a mail-in kit processed by a certified lab. Your county health department may offer subsidized kits.
See what’s in public water nearby
Nearby public systems draw on the same aquifers. Their results are a hint, not a substitute for testing. Look up a nearby town.
Questions
Is my private well tested by anyone?
No. Federal drinking water rules cover public water systems only. About 43 million Americans rely on private wells, and testing them is the owner's job.
How often should I test a well?
EPA and the CDC recommend testing at least once a year for total coliform bacteria, nitrate, pH and total dissolved solids, and more often if the water changes taste, smell or color, after flooding, or if there is a new baby in the house (nitrate). Test for arsenic, uranium, radon, lead, manganese and PFAS at least once, and again if nearby land use changes.
Should I test my well for PFAS?
If you live near an airport, military base, firefighting training site, landfill, wastewater sludge field or factory that used PFAS, yes. Use a lab certified for EPA Method 533 or 537.1. Home test strips cannot measure PFAS at the parts-per-trillion levels that matter.
Where do I get a well tested?
Your county or state health department often offers low-cost kits. Otherwise use a laboratory certified by your state for drinking water. Your state drinking water or environmental agency keeps the list of certified labs.