Well Water Testing Basics

Why should I test my well water?

Private wells are not checked by a public utility. Water can look and taste perfectly good while carrying bacteria, nitrate, arsenic, lead from plumbing or other substances that affect health. Testing gives you a baseline, a way to spot changes and a record that can matter if you sell the property.

Infants, pregnant women, older adults and people with weakened immune systems can be more affected by some contaminants. If any of them live in your home, ask a doctor or your county health office whether additional testing makes sense.

What should the water be tested for?

There is no single test list that fits every well. Local geology, nearby farms, old mines, industry, road salt and septic systems all change which substances show up. Your county health department or state drinking water program can tell you what is commonly found around you and which tests they recommend.

Many people begin with bacteria, nitrate and a general panel of minerals and pH. Others add metals, radon in water or pesticides depending on the area. Let the health office guide the list rather than guessing or buying a random package.

Some people also test more often if a household member has a health condition affecting immunity, or if livestock, a septic system or crop fields are close to the well. Share those details with the health office so the advice fits your actual setting.

• Bacteria: a sign of surface contamination
• Nitrate: linked to fertilizer, manure and septic systems
• General minerals and pH: affect taste, scale and corrosion
• Area-specific items: ask your health office

How do I choose a lab?

Use a laboratory certified or accredited by your state for drinking water analysis. Your state environmental or health agency usually keeps a list. A certified lab will send the right bottles, explain how to collect the sample and tell you how fast it must be returned.

Be careful about sales visits and free tests offered by companies that also sell treatment equipment. Get an independent lab result first, then decide whether you need any equipment at all.

How do I collect a sample properly?

Follow the lab instructions exactly. Sample bottles for bacteria are often sterile and must not be rinsed or touched inside. You may be asked to remove an aerator, run the water for a set time or collect from a particular tap. Small mistakes can contaminate a sample and give a misleading result.

Many samples have a short time limit between collection and arrival at the lab, so plan the day. Avoid collecting just before a weekend or holiday unless the lab says that is fine. Label the bottles clearly and fill out the form completely.

• Read the instructions before opening any bottle
• Use the tap the lab recommends
• Keep the sample cool if told to
• Deliver or ship it within the lab time limit

When should I test again?

Testing once is a start, not a finish. Health departments and EPA guidance generally encourage regular testing, with the exact schedule depending on the substance and your situation. Ask your county office how often they suggest for your area rather than relying on a rule of thumb.

Test again after flooding, a nearby spill, well repairs, changes in taste or smell, a new baby or pregnancy in the home, or when your neighbors report a problem. Also test again after installing treatment, to confirm it works.

What do I do with the results?

The lab report will list each substance and its measured level, often next to a health or aesthetic standard. Do not panic over a single flagged line, and do not ignore it either. Call your county health department or the lab and ask what the result means for drinking, cooking and bathing.

If a result raises a health concern, ask what to use for drinking water in the meantime and whether to retest. Treatment choices come after that, and an independent professional can help you match equipment to the problem.

What does testing usually cost and who can help pay?

Prices vary by lab and by which tests you choose, so ask for a quote before you collect anything. Some county health departments, extension offices or state programs offer low cost testing days or help for households that qualify. Ask yours whether any exist in your area.

Also ask whether your lender, a home sale or a nearby contamination event triggers any special testing requirement. Requirements differ by state and county, so confirm with the local health office instead of relying on what a neighbor remembers.

Keep every lab report, bottle receipt and note in one place. Over years, those pages become a record of how your water has behaved, and they help whoever buys the property after you.

Last reviewed: November 12, 2026. Written by the Rural Farm Life Editorial Team. See our editorial policy.