Abstract
Wastewater reclamation is one of most effective countermeasures for water shortage in the urbanized area. However, there are high infectious risks without the appropriate treatment of wastewater due to a huge number of pathogens. In this study, infectious risks by poliovirus through wastewater reclamation in the Abukuma watershed were evaluated under various scenarios. For predictive evaluation of water shortage in the watershed, fluctuations of river flow rate at the intake point of drinking water were represented with the matrix of simultaneous probability of flow rates in consecutive two days. Water qualities (total coliforms and SS) were also determined with matrices between river flow rate and them. When the inactivation efficiency of poliovirus by disinfectionwas higher than 3 logs, the damage of water shortage could be decreased by wastewater reclamation without any increase of infectious risk. In case of lower inactivation efficiency, infectious risks would exponentially increase with decrease of damage of water shortage. In the worst case in reclaiming secondary effluent, wastewater reclamation for decreasing 500 % day of damage of water shortage caused ten times as high infectious risk as that without reclamation.
