Public Health Evaluation of Advanced Reclaimed Water for Potable Applications

Abstract

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.

Reduction of Enteric Microorganisms at the Upper Occoquan Sewage Authority Water Reclamation Plant

“…It was found that microorganism reductions were a result of physical removal and that protozoa remained viable. Therefore, the high pH did not affect the viability of the protozoa as it did the viruses (Rose et al, 1999).…”

ChemInform Abstract: Health Effects Associated with Wastewater Treatment, Disposal, and Reuse

“…Under experimental conditions all three disinfectants met the WHO microbial guidelines. Tampa, Florida investigated the use of highly treated reclaimed water for potable applications (Rose et al, 1999). Removal and inactivation of viruses (99.99%), bacteria (99.9999%) and enteric protozoa (99.9%) were achieved.…”