Private Well Water
Start here if your water comes from a private well.
A well-water result is usually a testing and interpretation problem before it becomes a filter-shopping problem. Use this page to set a baseline, spot the issues that need retesting, and jump into the right contaminant guides.
Annual baseline: what to test even before you know the full problem
- Test at least annually for total coliform bacteria, nitrates, pH, and total dissolved solids as a baseline starting point.
- Add arsenic, lead, PFAS, or other location-specific contaminants when your region, land use, or local health department guidance makes them plausible.
- Retest after flooding, major well repairs, changes in taste or appearance, or after any positive bacteria result.
This baseline follows the CDC's July 1, 2024 well-water testing guidance: annual total coliform, nitrates, pH, and total dissolved solids, with extra contaminants added from local risk context.
When to slow down and retest before buying treatment
Do not jump straight to product shopping when the result shows bacteria, a fresh flooding event, a questionable sample process, or a new result that does not fit previous well history.
Use retesting and well inspection first when the problem may be a structural entry point, plumbing-side contamination, or an unstable one-time event rather than a steady contaminant profile.
Follow the contaminant path that matches your report
Bacteria / Coliform
Start here if the lab mentions total coliform, E. coli, or repeat disinfection questions.
Nitrates
Important when agricultural runoff, septic influence, or infant-risk decisions are part of the picture.
Arsenic
A lab-confirmed issue that usually needs contaminant-specific treatment planning rather than generic whole-house filtration.
PFAS
Use this when your lab or local reporting calls out PFAS compounds and you need certified drinking-water treatment options.
When Filter Finder becomes useful
Use Filter Finder after you know the contaminant category, the treatment scope, and whether you are solving a whole-house problem or a drinking-water problem. That sequence matters because well water often mixes testing questions, nuisance issues, and real health-risk contaminants in the same property.