Modelling of Surface Water Quality and Spatial Mapping in Mahanadi Basin, Odisha

Abstract

This study aimed at evaluating the surface water quality within the urban reach of Mahanadi River basin in Odisha. For this study, yearly water quality data were acquired from the State Pollution Control Board between low flow (between June and August) and high flow (between November and January) periods as part of a 5-year (2016–2021) monitoring programme (measuring 11 variables at 21 primary sites), to conduct an integrative investigation into the hydrogeochemical mechanisms that affect the water quality for drinking. Different methods like Multivariate Statistical Techniques (MST) such Pearson Correlation Matrix (PCM), Hierarchical Cluster Analysis (HCA), and Principal Component Analysis/Factor Analysis (PCA/FA) were applied. However, the relationship between the various factors revealed that anthropogenic activities and physicochemical parameters directly affect the fundamental ionic component of the water samples. Furthermore, with the help of plots, HCA was carried out and divided the 21 sampling sites into three major groups to verify the factor analysis results. Additionally, factor analysis has been conducted and four factors were extracted. Hence, the four components accounts for 87.17% and 67.22% of the total variance of the data composition for both seasons i.e., LFP and HFP, explaining the causes of water quality degradation. The four factors account for ‘salinity’, ‘hardness’, ‘domestic sewage’ and industrial effluents properties and were named accordingly. These factors revealed about point-based contamination, such as wastewater from commercial and residential sources, non-point sources, including such farm crops, and natural phenomena, such as inundation, rock, and soil disintegration. Further, this ongoing investigation also sheds light on core procedures, municipal regulations, and continual pollution monitoring to reduce the amount of pollution entering the river from both diffuse and point sources.