Development of Canadian Water Quality Index (WQI) of Vidhyadhari, an Estuarine River in Eastern India

Surface water represents one of the most utilized sources for water distribution systems globally, despite the fact that rapid urbanization and industrialization has reduced its cleanliness. As a result, the end-user's health is seriously impacted by the dirty water. Nevertheless, it is clear that many developing nations, including India, pay little regard to or care about this crucial issue. The Vidhyadhari River has become a receiver of high organic and bacteriological load of entire Kolkata City through Basanti canal. As a result, the purpose of this investigation is to evaluate how rapid urbanization and industrialization has changed the water quality of Vidhyadhari River using Canadian Water Quality Index (WQI). We have used seasonal water quality data collected at two monitoring stations (Haroa bridge and Malancha) from 2011 to 2020 to study the water quality of Vidhyadhari River. Results of the study indicated that the annual WQI value of Haroa brigde ranged between 21.62 (very bad) and 62.89 (medium) with an average of 27.29 (bad), whereas annual WQI value of Malancha station ranged between 15.44 (very bad) and 43.09 (bad) with an average of 18.77 (very bad). In comparison to downward location, the water quality of Vidhyadhari River was somehow good at upstream i.e., Haroa brigde. According to WQI, the water quality of Vidhyadhari River fall into bad to very bad category, which indicated deterioration of river water quality. Factor analysis revealed that both stations are predominated by hardness cluster (hardness, calcium, magnesium and chloride) followed by cluster of total dissolved solids (TDS), sulphate and ammonia. Sewer, excessive human activity, industrial discharges, poor sanitation, and urban runoff outflow can be extrapolated as the main causes for the deterioration of Vidhyadhari River water quality. This study emphasized the significance of implementing measurement actions, introduction of watershed characteristics and implications for developing water management strategies.