What should you test well water for?
Short answer: Every year, test for total coliform bacteria, nitrates, total dissolved solids and pH, as the EPA and CDC recommend. Then add tests based on where you live: the CDC suggests asking your health department about volatile organic compounds, lead, arsenic, mercury, radium and pesticides, and the EPA ties nearby activities like farming or mining to specific tests.
Every year
- Total coliform bacteria: an indicator that harmful germs may be present. You can also test for fecal coliform or E. coli; a positive result likely means feces have entered the well. [source]
- Nitrates: the CDC says all well owners should test for nitrates at least once a year. [source]
- Total dissolved solids and pH: indicators of scaling, taste and whether water may corrode pipes and release metals like lead. [source]
Ask your health department about
The CDC lists volatile organic compounds, lead, arsenic, mercury, radium, pesticides or herbicides, and other chemicals or germs, depending on where you live. [source]
Match tests to what's nearby (EPA)
| Condition or nearby activity | Test for |
|---|---|
| Recurring gastrointestinal illness | Coliform bacteria |
| Plumbing or service lines that contain lead | pH, lead, copper |
| Radon in indoor air or a radon-rich region | Radon |
| Corrosion of pipes or plumbing | Corrosion, pH, lead |
| Intensive agriculture nearby | Nitrate, nitrite, pesticides, coliform bacteria |
| Objectionable taste or smell | Hydrogen sulfide, corrosion, metals |
Source: EPA's table of conditions and recommended tests. [source]
Packages that bundle these
Penn State's standard package ($60) covers total coliform, E. coli, pH and total dissolved solids; its Agriculture/Septic package ($70) adds nitrate-nitrogen. [source] Virginia's VAHWQP clinic kit ($70) covers 28 constituents, including nitrate, lead and arsenic. [source] New Jersey's PWTA sets the required list for home sales in that state. [source]
FAQ
What should I test my well water for?
Every year, test for total coliform bacteria, nitrates, total dissolved solids and pH, as the EPA and CDC recommend. Then add tests based on where you live: the CDC suggests asking your health department about volatile organic compounds, lead, arsenic, mercury, radium and pesticides, and the EPA ties nearby activities like farming or mining to specific tests.
Does a standard well test include lead?
Not always. Penn State's $60 standard package covers coliform, E. coli, pH and TDS; lead is in its $125 package. Virginia's $70 VAHWQP kit includes lead.
Who can tell me what's common in my area?
The EPA and CDC both say your local health department can tell you which contaminants are common in your area's groundwater.
Sources
- CDC – Guidelines for Testing Well Water (accessed 2026-10-23)
- US EPA – Protect Your Home's Water (accessed 2026-10-23)
- Penn State AASL – Drinking Water Testing (fees) (accessed 2026-10-23)
- Virginia Household Water Quality Program (Virginia Tech/VCE) (accessed 2026-10-23)
- NJDEP – Private Well Testing Act (PWTA) (accessed 2026-10-21)
Informational only, not health, medical, legal or real-estate advice. Programs and fees change; confirm with the official source. See our disclaimer and affiliate disclosure.