Since the early 1900's, ozone has been the primary disinfectant in
European municipal water treatment. As in the US, much of the supply of city water in
Europe is from surface sources. Because chlorine produces proven carcinogenic disinfection
by-products called trihalomethanes (THM's) when it reacts with organic substances common
to surface water sources, ozone has been the treatment of choice in a rapidly growing
number of US cities. Los Angeles, for example, installed the largest ozone water treatment
plant in the world (600 million gallons per day) in the early '90's. Other large cities,
including New York, and some 2,000 other US communities, utilize ozone for primary
disinfection.
Support for Ozone by US EPA
The recent adoption of the Surface Treatment Rules by the United
States Environmental Protection Agency places strict limits on disinfecting by-products
(DPB's), including THM's. Because ozone products fewer DPB's the EPA, along with the
American Water Works Association, has emphasized the use of the ozone as a highly
desirable water treatment alternative for small communities as well as large.
Cryptosporidium parvus, commonly called Crypto, a recently
discovered microbe common to up to 86% of all municipal water sources, is eliminated only
by either ozone or submicron filtration. It is completely impervious to chlorine. Crypto
first was widely acknowledged as a public health threat when an infestation rendered the
city of Milwaukee, Wisconsin infected, resulting in a reported 100 + deaths.
Ozone, A Natural Disinfectant

Oxygen .................................... Ozone
Ozone, is a pale blue tri-atomic form of oxygen. It is formed in
nature by lightning and by the ultraviolet bombardment of oxygen molecules by sunlight.
Man-made ozone is formed by passing dry ambient air or oxygen
through a high voltage field called a corona, which is produced inside an ozone generator.
The high voltage breaks apart the oxygen (02) molecules and causes them to reform as Ozone
(03), which is up to 13 times more soluble in water than oxygen.
When the ozone is dissolved in water, it's unstable nature makes it
highly reactive with oxidizable mineral, organic and microbiological contamination. Unlike
chlorine, which merely deactivates bacteria after lengthy exposure time, ozone literally
destroys bacteria on contact. The end product of ozone oxidation of organic matter is
carbon dioxide and water. Ozone oxidizes mineral contaminants from a soluble form to an
insoluble form, to permit final removal by filtration.
After ozone has done its job, it reverts back to pure oxygen, making
it the most powerful non-chemical water treatment technology available.