EPA sets the standard of zero colonies of
fecal coliform bacteria per 100ml of water to determine the possible
presence of other disease causing bacteria, viruses, and protozoans that
Water Contaminated with the fecal coliform indicator
bactiera must be treated and disinfected before ingestion to prevent
The microorganisms that are of highest concern include
Cryptosporidium parvum, Giardia duodenalis, Campylocbacter spp., Salmonella
spp., pathogenic strains of E. coli, and Yersinia spp.
What are some of the methods used to treat and disinfect
water containing these organisms?
The two most reliable methods to my knowledge are,
chlorination which is the
chice in most of the USA and ozonation which is the choice in other
countries such as France ( as I remember). I prefer the ozonation because
it is , in my opinion, safer because it will produce less side reactions
with such things as tannins that are commonly benign product of leaves and
organic matter in wells.
Although Chlorination is used to inactivate certain organisms in water,
filtration is highly important in "removal" of such since Cryptosporidium parvum
is highly resistant to the widely used disinfectant.
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Update: June 2012