Characteristics of Fecal Indicators in Channels of Johkasou Systems

Abstract

A johkasou system is getting popular as a decentralized wastewater treatment system in low-density communities. Treated waters of the johkasou systems, which are generally discharged into channels within residential areas before entering the local receiving water body, may contain microbial contaminants. To identify the characteristics of fecal indicators in the channels of the johkasou systems, the concentrations of fecal indicators (F-RNA bacteriophages, GIII F-RNA bacteriophages, Escherichia coli, and total coliforms) were examined both in water and sediment in the channels of three johkasou systems. These fecal indicators were always detected at high levels both in water and sediment in the channels of three johkasou systems through the study period. Significant differences in concentrations of fecal indicators were not observed among three johkasou systems in different residential areas. Concentrations of fecal indicators fluctuated in a day mainly due to domestic activities. Significant positive correlations of total coliforms and E. coli in water with total coliforms and E. coli in sediment suggest the potential importance of sediment on microbial dynamics in the channels of the johkasou systems. No significant correlations of F-RNA bacteriophages with total coliforms and E. coli indicate a specific distribution mechanism for F-RNA bacteriophages.

Distribution of Fecal Indicator Bacteria in Sediment of Local Open Channels Receiving Johkasou Effluent

“…Previous studies reported that high concentrations of total coliform and E. coli were recorded in both water and sediment of channels receiving effluents from Johkasou, an advanced onsite domestic system in Japan (Setiyawan et al, 2014). That high concentration of fecal indicators was still observed although during high flow condition which indicates less hydrological influenced on the fecal indicator in rural areas (Jamieson et al, 2003).…”

Seasonal Characteristics of Fecal Indicators in Water Environment Receiving Effluents of Decentralized Wastewater Treatment Facilities

“…Several studies have also highlighted the seasonal differences in the microbiological quality of surface water quality due to numerous factors such as the unequal loading of wastewater, solar irradiation, temperature, water flow, dilution, rainfall, organic matter, and the origin of the microorganisms 15,16) . In the previous study, fecal indicators have been detected in the channels of johkasou systems 17) . However, the seasonal characteristics of fecal indicators in the local water environment receiving johkasou effluents are little known.…”

Viral indicators for tracking domestic wastewater contamination in the aquatic environment

“…The PMMoV titre was assessed in wastewater samples derived from the USA, Germany, New Zealand and Vietnam (Hamza et al, 2011;Kitajima et al, 2014;Kuroda et al, 2015;Rosario et al, 2009;Schmitz et al, 2016;Symonds et al, 2016). FRNAP-II prevalence in wastewater was only assessed in Japan and Ireland (Flannery et al, 2013;Haramoto et al, 2015Haramoto et al, , 2012Lee et al, 2018), while FRNAP-III prevalence in wastewater was only assessed in Japan (Haramoto et al, 2015(Haramoto et al, , 2012Lee et al, 2018;Setiyawan et al, 2014Setiyawan et al, , 2013. In wastewater, the concentrations of phages associated with Bacteroides BG-124 were assessed in the USA, Brazil, the UK (England) and Switzerland (E. Dias et al, 2018a;McMinn et al, 2014;Prado et al, 2018;Purnell et al, 2015;Stefanakis et al, 2019;Wicki et al, 2015), BacRYC 2056P were investigated in Colombia, the UK, Spain, France, Cyprus, Sweden, Switzerland and Thailand (Cost an-Longares et al, 2008;Gomila et al, 2008;Payan et al, 2005;Venegas et al, 2015;Wangkahad et al, 2017;Wicki et al, 2015Wicki et al, , 2011, BacGA17P were found in Colombia and several European countries (Casanovas-Massana et al, 2015;Cost an-Longares et al, 2008;Gomila et al, 2008;Mayer et al, 2016;Payan et al, 2005;Venegas et al, 2015;Wicki et al, 2015) and BacARABA84P was identified in Switzerland...…”