Spatio-Temporal Assessment of Surface Water Quality of Torsa River in Cooch Behar Municipality, Its Adjacent Areas, and Outskirts, West Bengal, India Using CCME-WQI

Abstract

Water is a vital resource for sustaining life, and its quality is of utmost importance for the well-being of both humans and ecosystems. Rivers serve as significant sources of freshwater, providing drinking water, irrigation, and supporting various aquatic habitats. An attempt has been made in this paper to show the spatio - temporal variation of water quality along the Torsa River at Cooch Behar Town, its adjacent areas and outskirts, West Bengal, India. The field work was conducted during Pre-Monsoon, Monsoon, Post-Monsoon and Winter in the year of 2022 and 2023. To carry out the study, water samples have been collected from 5 stations, one station from urban environment, two from adjacent to urban environment, and two from outskirts. The collected samples have been tested in the laboratory by titration, gravimetric and coloration method. CCME WQI was applied using thirteen water quality parameters namely Temperature, pH, Conductivity, Turbidity, Total Hardness, Total Dissolved Solids, Total Soluble Solids, Dissolved oxygen, Biological Oxygen Demand, Chloride, Ferrous, Nitrate and Phosphate. Based on the results obtained from the index, the water quality of Torsa River ranged between 71.13 to 90.06 which indicate that river has the Fair to Good quality due to effect of various rural and urban pollutant sources. The temperature, turbidity, DO, BOD, Chloride and Phosphate do not meet the standards in different sampling stations especially in Monsoon. This makes the water unsuitable for drinking purposes without proper treatment. The work confirms the need to take an action for monitoring the river for proper management. Therefore, there is a need of intensive study leading to a contamination zone mapping to river water quality management.