Water quality assessment using the Pollution Index (PI) and statistical tools: a case study of Thi Vai river, Dong Nai, Vietnam

The quality of river water is influenced by two factors: nature and man. The aims of this paper are to determine the influence of anthropogenic sources of pollution on water quality, by assessing integrated measurements from use of the Pollution Index (PI) of Indonesia and diverse statistical techniques, including one-way analysis of variance (ANOVA) and ArcGIS. In this study, 10 physicochemical parameters for the determination of water quality, from surface water taken the Thi Vai river, are examined: dissolved oxygen (DO), biochemical oxygen demand (BOD5), chemical oxygen demand (COD), ammonium (NH4+-N), phosphate (PO43--P); total dissolved solids (TSS), pH, nitrite (NO2-), nitrate (NO3-), total coliforms, and fecal E. coli. The samples were collected from seven monitoring sites, for assessing spatial and temporal water quality, in the three years 2015 to 2017. The findings revealed that water quality index values within the study area showed a significant pollution level for nitrite, and fecal E. coli. Water quality was detrimental at the sites TV2, TV3, and TV4. A further finding was that there was significant variation recorded between the two methods of measuring PI - that of the Ministry of the Environment, Indonesia, and that of Vietnam. Finally, this integrated technique could, it is suggested, be an effective approach for communicating information on water quality for sustainable waste management in Thi Vai river.