Public Health Evaluation of Advanced Reclaimed Water for Potable Applications

The City of Tampa in the Southwest portion of Florida is examining the development of an advanced treatment facility for supplementing their potable water supply with highly treated reclaimed water. Full-scale microbiological monitoring of a similar treatment train demonstrated that the high-pH chemical treatment process was an effective barrier for removal and inactivation of viruses (99.99%), bacteria (99.9999%) and enteric protozoa (99.9%). A constructed pilot plant and bench-scale studies of the high-pH chemical process demonstrated that the removal of Cryptosporidium oocysts was due to physical removal and no inactivation was shown with up to 180 minutes exposure at a pH of 11.2. Combination of high-pH chemical treatment and chlorination were also ineffective at kill of Cryptosporidium oocysts.