Types of Water Testing

Water tests by category

Each test below sits under its category, with a price range from state-certified labs where we have verified one. Open a test to see who should run it, how to collect the sample and what your level means.

Types of water testing: categories and methods

There are two ways to sort the types of water testing: by what a test looks for, and by who runs it. The first tells you which tests your water needs. The second tells you how much weight the result can carry. EPA says private wells are not regulated under the Safe Drinking Water Act or by most state governments, so for a well both choices are yours.

By what the test looks for

• Bacteria. CDC recommends testing a well at least once every year for total coliform bacteria. A high count makes it likely that harmful germs are also in the water, and a positive fecal coliform or E. coli test likely means feces have reached the well.
• Metals. EPA's list of heavy metals includes arsenic, copper and lead, which can come from household plumbing and natural mineral deposits. Our lead, arsenic, iron and manganese tests sit in this group.
• Nitrate and nitrite. EPA says these come from fertilizers, sewage and animal waste and are most serious for infants. CDC says every well owner should test for nitrates at least once every year.
• Other inorganic chemicals. EPA's primary standards group inorganic chemicals together, and EPA notes that fluoride is present in many aquifers and can be found in private wells.
• Radioactive contaminants. EPA describes radionuclides as radioactive forms of elements such as uranium and radium, which may be naturally present in ground water in some areas.
• PFAS. EPA's primary standards list selected PFAS as their own group, apart from other organic chemicals.
• Volatile organic compounds. CDC calls VOCs industrial and fuel-related chemicals and says which ones to test for depends on where you live.
• Physical properties. These describe the water itself. CDC says pH tells you how acidic or basic water is and total dissolved solids how much "stuff" is mixed in, and USGS defines hardness as the amount of dissolved calcium and magnesium.
• Taste, odor and staining. EPA's secondary standards cover tastes, odors and staining. They are guidelines that EPA does not enforce.

CDC suggests asking your local health department which of these to test for where you live. If you are not sure, the water test finder asks a few questions about your water and suggests the tests that fit.

By who runs the test

• A state-certified lab. CDC's advice is to use a state-certified laboratory. It reports a measured level for each contaminant, which you can compare with the benchmark for it. Our home page explains where to get your water tested.
• A mail-in kit. Purdue Extension notes that some kits come with containers and a mailing label for sending the sample to a laboratory, and that if the lab is certified and you follow all instructions, the results are generally reliable.
• Test strips and home kits. Purdue Extension calls do-it-yourself kits a simplified version of a lab's tests, useful as a screen for whether further testing is needed. A positive result should be followed up with a test from a certified laboratory.

Lab prices vary by test and by lab; our well water testing cost guide compares them.