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Q. I have Bacteria in my water. How can I get make my water safe to drink?
Disinfection technologies kill or screen-out biological contaminants present in a water supply. Chlorination, microfiltration, ozone, and ultraviolet light are the four major technologies used to disinfect water.
Chlorination
Chlorination adds a concentration of the chemical chlorine or chloramine
to the water supply, where the oxidizing ability of this chemical ''burns
up'' the organic contaminants in the water. Chlorination also treats for
organically-related taste, color, and odor problems.
Chlorine is typically fed directly into a well, or into a retention tank
where concentration and contact time can be controlled. Chlorination is
effective for treating pathogens like coliform bacteria and legionella,
though it is ineffective against hard-shelled cysts like Cryptosoridium
and Giardia lamblia. Other chemicals like bromine and iodine can also be
used to disinfect water through much the same process as chlorination, though
they are not as frequently used.
Microfiltration
Microfiltration uses a filter media with a pore size smaller than 0.2 microns
to physically prevent biological contamination from passing through. Ceramic
and solid block carbon as well as reverse osmosis membrains are commonly
used to provide microfiltration. Ceramic filters have an advantage that
they can often be cleaned and reused a number of times before they lose
effectiveness.
Carbon block media usually has to be disposed of after each use. This media,
however, provides additional treatment for a variety of other health and
aesthetic contaminants (see activated carbon section, above). Microfiltration
is effective for treating the full range of biological contaminants, including
hard-shelled cysts like Cryptosporidium.