||Isolating Viruses from Finished Water.
Rose, J. B. ;
Gerba, C. P. ;
Singh, S. N. ;
Toranzos, G. A. ;
Keswick, B. ;
||Arizona Univ., Tucson. ;Texas Univ. Health Science Center at Houston.;Health Effects Research Lab., Research Triangle Park, NC.
Water treatment ;
Coliform bacteria ;
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
The reduction of enteroviruses and rotaviruses was studied at a full scale 205 mgd water treatment plant involving chemical flocculation, sand filtration and chlorination. Reduction of enteroviruses and rotaviruses averaged 81% and 93%, respectively, for the complete treatment process. The greatest reduction of enteroviruses occurred during prechlorination/flocculation and filtration, while the greatest reduction of rotaviruses occurred during pre-chlorination/clarification and final chlorination. Although major plant deficiencies may have been responsible for occurrence of viruses in the finished water, the results of the study indicate that finished water having measureable levels of free residual chlorine and meeting standards for coliform bacteria and turbidity cannot be assumed to be virus free.