Routine Private Well Testing
Private wells aren't monitored by anyone but you. A routine testing calendar is the only way to know what's actually in your water.
Short answer: Test annually for bacteria at minimum, and periodically for a broader panel (nitrate, VOCs, arsenic, gross alpha/uranium, iron/manganese, pH, and PFAS where relevant) through an NJ-certified laboratory. This is separate from mandatory Private Well Testing Act sampling tied to a real-estate transaction.
Who this is for: private-well homeowners who want to build an ongoing, non-transaction testing routine.
New Jersey context
New Jersey's geology drives regional concerns that vary by area: coliform bacteria and E. coli, nitrate, volatile organic compounds, arsenic, gross alpha activity, uranium, radium-related concerns, iron and manganese, pH, PFAS, and, in some coastal areas, sodium or chloride from saltwater intrusion. None of these should be assumed present or absent at your specific property without a test.
A basic testing calendar
- Annually: total coliform bacteria and E. coli
- Every few years, or after any noticeable change in taste, odor, or color: a broader panel including nitrate, VOCs, arsenic, iron, manganese, and pH
- At least once, and again if regional data suggests elevated risk: gross alpha activity, uranium, and radium-related parameters
- If you are near a known contamination source or coastal area: PFAS and/or sodium/chloride testing
- After any treatment installation: retest to confirm the system is working as expected
Common mistakes
- Testing once at move-in and never again
- Assuming a neighbor's result applies to your well
- Skipping retesting after treatment is installed
When professional help is appropriate
Use an NJ-certified laboratory for all testing. A well contractor can help with well records, permits, or physical well issues; a treatment provider can help only after you have a specific result to address.
Official sources
- NJDEP Private Wells program
- NJDEP certified laboratory directory
Related
- Find an NJ-Certified Lab
- Understanding Well Test Results
- NJ Private Well Testing Act (for transactions)
Is there a state-mandated schedule for routine well testing?
Routine (non-transaction) private-well testing is generally left to the homeowner in New Jersey. Confirm any current local health department recommendations, since some counties or municipalities may offer specific guidance.
This page provides general educational information and is not medical or laboratory advice.
Last reviewed: 2026-07-11. Report a correction.