Why are unfiltered water systems required to add treatment?
Existing regulations did not require unfiltered systems to provide any treatment for Cryptosporidium. Although unfiltered systems maintain watershed control programs to protect water quality, recent surveys have shown Cryptosporidium to be present in the sources of unfiltered systems. Without treatment, these Cryptosporidium will pass into the water distributed to consumers. Available data indicate that the average risk from Cryptosporidium in unfiltered systems is higher than in filtered systems, so that treatment by unfiltered systems is required to achieve comparable public health protection. Further, with available technologies like UV and ozone, treatment for Cryptosporidium is feasible for all unfiltered systems. Consequently, EPA is establishing requirements under the LT2ESWTR for all unfiltered systems to treat for Cryptosporidium, with the required degree of treatment depending on the source water contamination level. Top of page Where can I find information on contacting a la
