Well Water
Testing Frequently Asked Questions
Should I
have my well tested?
Yes. In 1999 - 2000, contaminated private well water caused 26% of the
drinking water outbreaks that made people sick. The U.S. Environmental
Protection Agency's (EPA) rules that protect public drinking water systems
do not apply to privately owned wells. Most states have rules for private
wells, but these rules may not completely protect your private well. In
other words, as a private well owner, it is up to you to make sure that your
well water is safe to drink. Your local health or environmental department
can help advise you.
When should
I have my well tested?
Check your well every spring to make sure there are no mechanical problems;
test it once each year for germs and once every two to three years for
harmful chemicals. 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 (i.e.,
flooding, land disturbances, and nearby waste disposal sites)
-
You replace or repair any part of your well system.
How do I
find out if my well is contaminated?
The only way to find out if your well water is contaminated is to test it.
You can contact your health or environmental department, or a private
laboratory to test for germs and harmful chemicals. In some states, the
drilling contractor must test a new well after it is built. However, as a
well owner, it is up to you to maintain your well and have it tested
regularly.
How do
germs and chemicals get into my well water?
Germs and chemicals can get into your well water and contaminate it in
different ways. Some germs and chemicals occur naturally. For example, heavy
metals like arsenic, lead, and cadmium are naturally found in rocks and soil
and sometimes seep into ground water. Other contaminants come from human and
animal waste resulting from polluted storm water runoff, agricultural
runoff, flooded sewers, or individual septic systems that are not working
properly.
What are
the germs and chemicals I should test for in my well?
Several things you should test for are listed below. These germs and
chemicals can be a risk to your health. (Please see the
Contaminants in Well Water fact sheet for a list of common germs and
chemicals in drinking water and the illnesses they cause.)
Total
Coliform
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
Coliform / Escherichia coli (E. coli)
Fecal coliform bacteria are a 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 E. coli with a test
for the more dangerous E. coli O157:H7.
Nitrate
Nitrate is naturally found in many types of food. However, 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. The presence of nitrate in well water also depends on the
geology of the land around your well. A nitrate test is recommended for
all wells. If the nitrate level in your water is higher
than the EPA standards, 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 at certain levels. Which VOCs to test for depends on where you
live. Contact your local health or environmental department, or the EPA to
find out if any VOCs are a problem in your region. Some VOCs to ask about
testing for are benzene, carbon tetrachloride, toluene, trichloroethelene,
and methyl tertiary butyl ether (MTBE).
pH
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 leak out of the pipes into the water, and eventually
make you sick.
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 could include testing for lead, arsenic,
mercury, radium, atrazine, and other pesticides. You should check with your
local health or environmental department, or the EPA to find out if any of
these are a problem in your region.
Please remember
that if your test results say that there are germs or chemicals in your
water, you should contact your local health or environmental department for
help and test your water more often.
My well
water has a funny smell or taste; should I worry about getting sick?
A change in your water's taste, color, or smell is often not a health
concern. However, a change could be a sign of serious contamination
problems. Any time you notice a change in your water quality, you should
have it tested.
Where do I
go to have my well water tested?
State and local health or environmental departments often test for bacteria
and nitrates. 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.
Others who may be
able to provide you with this listing include:
Revised Summer 2003 |
