When granular activated carbon is used, the filter will remove man-made organic compounds such as pesticides, herbicides, and other natural organic compounds that can cause taste and odors. As recommended by the American Dental Association and the VDH, fluoride is added as a tooth decay preventative. Finally, to maintain water quality throughout the distribution network, and minimize the formation of disinfection byproducts, chloramines are added to maintain a disinfectant residual. The treated water proceeds through a series of pressure controls and storage facilities before being delivered to your home. Use of Chlorine and Ozone Over the past century, the water industry has used chlorine to destroy harmful bacteria that may be present in the surface waters, such as rivers, lakes and reservoirs.
Chlorine is highly reactive.
When added to these waters, chlorine reacts with the natural organic material and forms disinfection by-products. Some people, who drink water containing disinfection by-products in excess of the MCL over many years, may have an increased risk of getting cancer. The EPA has a current standard for a group of by-products known as Trihalomethanes. This MCL is set at 100 ppb. The MCL for the HAA's will be 60 ppb.