How Often Should You Test Your Well Water?
Every year
EPA recommends testing private wells every year for total coliform bacteria, nitrate, total dissolved solids and pH. Spring, after snowmelt and rain, is a common time to test.
Right away
- After flooding, or if floodwater reached the wellhead.
- After well repairs, a new pump, or any work that opens the well.
- If taste, color or smell changes.
- If someone in the house has repeated stomach illness.
- Before a baby comes home, or during pregnancy.
Every few years
EPA's RadTown page recommends testing for radionuclides every three years. Repeat tests for arsenic, uranium, manganese or other local concerns as your lab or health department advises.
Set a reminder
Our free testing reminder tool downloads a calendar file with yearly alerts.
Sources
- EPA: Protect your home's water
- EPA RadTown: Natural radionuclides in private wells
- EPA: What to do with your private well after a flood
Questions
How often should I test for bacteria?
At least every year, and right away after floods, well work, or a change in the water.
Free well water safety checklist
15 family-friendly steps based on CDC and EPA guidance. Print it, keep it on the fridge, and know when to call a certified lab.
More guides
- Flood Protection for Well Owners: Before, During and After a FloodRaise and seal the wellhead, know your pump shutoff, then disinfect and test with a certified lab after any flood.
- PFAS “Forever Chemicals” in Private Wells: Why You Should TestFederal PFAS rules protect public water systems — not private wells. Here’s what “forever chemicals” mean for well owners and how to get tested.
- Nitrates in Well Water and Blue Baby Syndrome: Who Must TestNitrate in well water can cause blue baby syndrome in infants. Learn who is at risk, when to test, and how to find a certified lab.
- Arsenic in Private Well Water: The Invisible Risk UndergroundArsenic in groundwater is often naturally occurring and invisible. USGS research shows millions of private-well users may be above the EPA drinking-water standard.