Test private-well water through a certified laboratory
Private well owners are responsible for checking water quality, and contamination may not change taste or appearance.
When it usually needs attention
Usually repeats every 1 year
CDC recommends annual baseline testing, with local authorities selecting additional analytes.
When this guide applies
Applies only to a confirmed private well.
What to do
Ask the local health authority which analytes apply, use a certified laboratory, and preserve the result and sample date.
Applies when: Applies only to a confirmed private well.
Who should handle it: Responsibility may belong to the owner, association, or shared-well operator; tenants report concerns.
Tools
- Certified laboratory sampling kit and instructions
Parts and supplies
- Laboratory-provided sterile containers
Safety gear
- As specified by the laboratory for the sampling point
Before you start
- Certified laboratory
- Local analyte guidance
Power, water, or fuel shutoffs
- None unless the laboratory instructions explicitly require it
Cleaner or chemical limits
Do not rinse, sanitize, or substitute the laboratory container; follow its collection directions exactly.
Stop and get help when
- Do not open a well cap, enter a pit, or perform electrical/pump work
- Use event-specific public-health guidance after a flood or suspected contamination
Who to call: A certified laboratory analyzes the sample; qualified well service handles system work.
Reviewed sources
- Guidelines for Testing Well WaterCenters for Disease Control and Prevention · reviewed July 13, 2026