Well Water Testing


The U.S. Environmental Protection Agency’s (EPA) rules that protect public drinking water systems do not apply to individual water systems, such as privately owned wells.

Therefore, as an individual water system owner, it is up to you to make sure that your water is safe to drink.

What to test for in your well?
A WQI (water quality indicator) test is a test that measures the presence and amount of certain germs in water.

Several water quality indicators and contaminants that should be tested for in your water are listed below. In most cases, the presence of WQIs is not the cause of sickness; however, they are easy to test for and their presence may indicate the presence of sewage and other disease-causing germs from human and/or animal feces.

Examples of Water Quality Indicators:

Total Coliforms
Coliform bacteria are microbes found in the digestive systems of warm-blooded animals, in soil, on plants, and in surface water. These microbes typically do not make you sick; however, because microbes that do cause disease are hard to test for in the water, “total coliforms” are tested instead. If the total coliform count is high, then it is very possible that harmful germs like viruses, bacteria, and parasites might also be found in the water.

Fecal Coliforms / Escherichia coli (E. coli)
Fecal coliform bacteria are a specific kind of total coliform. The feces (or stool) and digestive systems of humans and warm-blooded animals contain millions of fecal coliforms. E. coli is part of the fecal coliform group and may be tested for by itself. Fecal coliforms and E. coli are usually harmless. However, a positive test may mean that feces and harmful germs have found their way into your water system. These harmful germs can cause diarrhea, dysentery, and hepatitis. It is important not to confuse the test for the common and usually harmless WQI E. coli with a test for the more dangerous germ E. coli O157:H7.

The pH level tells you how acidic or basic your water is. The pH level of the water can change how your water looks and tastes. If the pH of your water is too low or too high, it could damage your pipes, cause heavy metals like lead to leach out of the pipes into the water, and eventually make you sick.

Examples of Contaminants:

High levels of nitrate in drinking water can make people sick. Nitrate in your well water can come from animal waste, private septic systems, wastewater, flooded sewers, polluted storm water runoff, fertilizers, agricultural runoff, and decaying plants. A combination NITRITE & NITRATE test is recommended for all wells. If the nitrate level in your water is higher than the EPA standards (10 milligrams per liter (10 parts per million)), you should look for other sources of water or ways to treat your water.

Volatile Organic Compounds (VOCs)
VOCs are industrial and fuel-related chemicals that may cause bad health effects. Which VOCs to test for depends on where you live, for example; near an underground pipe line, abandoned gas station or an industrial facility. VOCs to consider testing for are benzene, carbon tetrachloride, toluene, trichloroethylene, and methyl tertiary butyl ether (MTBE).

Other germs or harmful chemicals that you should test for will depend on where your well is located on your property, which state you live in, and whether you live in an urban or rural area. These tests include testing for lead, arsenic, mercury, radium, atrazine and pesticides.

When to have your well tested

At a minimum, check your well every spring to make sure there are no mechanical problems; test it once each year for total coliform bacteria, nitrates, total dissolved solids, and pH levels. If you suspect other contaminants, you should test for those as well. The best way to start is to consult a local expert about local contaminants of concern.
You should also have your well tested if:

  • There are known problems with well water in your area
  • You have experienced problems near your well, for example; flooding or land disturbances such as digging and any nearby waste disposal site.
  • You replace or repair any part of your well system
  • You notice a change in water quality (i.e., taste, color, odor)

Who should test your well?

State and local health or environmental departments often test for nitrates, total coliforms, fecal coliform, volatile organic compounds, and pH (see above). Health or environmental departments, or county governments should have a list of the state-certified (licensed) laboratories in your area that test for a variety of substances.

AMERICAN ENVIRONMENTAL LABORATORIES can pull samples and perform appropriate tests for well water quality.