For people who rely on a private well: what to test, sample, and understand before you buy treatment.

Start with what you notice

Understand what’s happening with your well water.

Clear, independent guidance to help you identify common problems, choose the right tests, and understand your options before buying treatment.

What are you noticing? Plan a water test

No diagnosis by appearance. Start with evidence, then compare testing, professional help, and treatment options.

Urgent conditions

Know when to switch to another water source

Use another known-safe water source for drinking, cooking, brushing teeth, making ice and infant formula if floodwater reached the well, the cap or casing is damaged, fuel, chemicals or sewage may be involved, or people are ill and contaminated water is a reasonable concern.

Contact your state or local health department for location-specific testing and disinfection instructions. Call emergency services for severe symptoms or an immediate hazard.

From the well to the tap

See how water travels from your water well to the tap

If one bathroom tap has a problem but the kitchen does not, that detail matters. So does a change that appears only in hot water. Compare locations, write down the pattern, and use testing to sort out what to do next.

A person filling a clear drinking glass at a kitchen faucet — **At home**Changes in odor, color or clarity are often first noticed at the tap.

A water professional examining a clear sample bottle outdoors — **During testing**Collection technique matters. Follow the certified laboratory's instructions.

A truck-mounted water-well drilling rig at a work site — **At the well**Drilling, casing and structural repairs belong to qualified well professionals.

A practical order of work

Narrow down the cause before you buy equipment

A smell or stain gives you a clue, not a diagnosis. Record the pattern, get the water tested, then use the result to compare the next step.

Describe the problem clearly

Note when it began, which taps are affected, and whether you notice it in hot water, cold water, or both.

Compare common well water problems

Talk to the laboratory

Tell a state-certified drinking-water laboratory what changed. Ask what to test and follow its sampling instructions.

Prepare for certified well water testing

Use the result to shop carefully

Compare treatment using the result, the rest of the water chemistry, your flow needs, and the maintenance each option requires.

Compare well water treatment options

Your well system

If the change was sudden, check the wellhead for clues

Walk outside and look for standing water, recent excavation, storm damage, or a loose cap. Do not open the casing. If you find damage, call a qualified well professional.

Keep the casing above grade and direct runoff away.
Have a damaged cap or casing inspected by a qualified well professional.
Remember that clear appearance does not establish safety.

How our well water guidance works

Hand-painted cutaway of a rural farmhouse, a capped private-well casing and groundwater-bearing rock below — Explore five parts of a typical private-well setting. The illustration explains system function and cannot diagnose a well.

Evidence before products

Start with public health guidance for private water wells

When the question is health or safety, start with your health department and public agencies that do not sell water treatment equipment.