|
Testing
Your
Drinking
Water
Public water supplies are required to be tested at regular
intervals under the federal Safe Drinking Water Act. Suppliers
must provide water that meets the guidelines of the Act, or
immediately notify you if the water fails any of the tests.
Check your drinking water at least annually.
If you have a private well, it’s up to you to have the water
tested. You may not be required to have the tests run, but
annual checks will help insure safe, healthy water for your
family. Independent professional labs don’t sell filters or
other products. Their goal is to provide unbiased testing.
When problems are detected, labs can usually tell you where to
get more information on what can be done to resolve the issue.
Common Tests and
What They Tell You
Coliform Bacteria and E coli: Coliform tests are the
most important indicator of water safety. The test detects
contamination from sewage, surface water, and other sources that
may contain disease-causing bacteria. The test should be run at
least annually and the water should not be used for drinking or
cooking if either the Total Coliforms or the E. coli tests are
positive.
|
Nitrates: More than 10 ppm of
nitrate nitrogen is dangerous for infants and pregnant women,
causing a condition known as “blue babies.” Nitrates can come
from sewage or septic waste and fertilizers.
Lead: Lead is a toxic element and
should not be present in drinking water at levels greater than
15 ppb. Lead rarely originates in the water supply itself.
Contamination from lead solder is fairly common, and some older
homes may even have lead pipes. Some brass fixtures also leach
lead. Corrosive water leaches more lead.
Fluoride: Naturally occurring
fluoride is found in almost all well water. If your dentist is
prescribing fluoride for your children, she/he may want to know
how much you already have in your water.
Hardness: Hardness is not
considered a health threat, but high levels may cause an
unpleasant taste, lime deposits on plumbing fixtures, and
difficulty in washing. Soaps and detergents do not lather well
in hard water. Water softeners are available from many
suppliers.
Sodium: Sodium may be harmful to
people with heart or kidney disorders. Patients with high blood
pressure often must restrict their sodium intake. There is no
“normal” amount of sodium in well water. Natural sodium levels
in water range from a trace to hundreds of ppm, or even more.
Softeners add sodium to water.
Iron: Like hardness, iron is not
a health hazard, but can be a nuisance if high levels are
present. More than 0.3 ppm of iron may cause staining and may
impart a bitter taste.
 |
Manganese: The effects of manganese
are similar to those of iron. Levels over 0.05 ppm may cause
problems.
pH: pH indicates the
acid-alkaline nature of water. Neutral water has a pH of 7.0,
but values between 6.5 and 8.5 are considered acceptable. Above
pH 7, water is alkaline. Below 7, water is acidic.
Arsenic: The USEPA recently
lowered the Maximum Contaminant Level (MCL) for arsenic in
drinking water from 50 ppb to 10 ppb. Chronic health effects
can result even from low concentrations. Arsenic is also a
suspected carcinogen. Naturally occurring arsenic has been
found in groundwater in Minnesota at levels exceeding the MCL.
Volatile Organic Compounds: VOCs
include a group of solvents and other industrial chemicals, many
of which are regulated under the federal Safe Drinking Water
Act. They are not naturally occurring, but are sometimes found
in groundwater due to failed landfill operations, fuel spills or
leaks, or industrial operations.
Other Contaminants: There are
many other potential contaminants to drinking water. If you
have a specific problem, know of, or suspect a spill or source
of contamination, call a professional to discuss the problem and
determine if testing is advised.
 |
