ASSESSMENT OF THE EFFECT OF COVID-19 LOCKDOWN ONWATER QUALITY OF BALDI RIVER SAHASTRADHARA SULPHURSPRING, DEHRADUN, UTTARAKHAND, INDIAShail KulshresthaAbstract Due to imposed restrictions during COVID-19 lockdown on air- rail - road traffic and industrial activities,early signs of improvement in water quality of several Indian rivers were noticed in terms of higher dissolvedoxygen and lower biochemical oxygen demand and total Coliforms, on account of least discharge of industrialeffluents and restricted human outdoor movement. In the backdrop of above, this study was aimed toassess the water quality index (WQI) of Baldi River -Sahastradhara Sulphur Spring, Dehradun, India, byfollowing the U.S. National Sanitation Foundation, NSF-WQI model, during lockdown (April to June 2020)and after unlocking process (July â September, 2020). The spatial and seasonal variations in ten waterquality parameters of Baldi River -Sahastradhara Sulphur Spring were investigated by monitoring thewater quality at three locations; Baldi river upstream, Sahastradhara proper and Baldi river downstream. Duringthe entire study period, improved water quality was observed, in terms of high DO ranging from 9.17±0.035to 8.38±0.028 mg/L and comparatively low BOD ranging from 1.68±0.032 to 2.31± 0.031 and low totalcoliform counts ranging from 06±1.09 to 31±2.75 MPN/100 mL. The NSF-WQI water quality status ofBaldi River -Sahastradhara Sulphur Spring was found to be Good all the time and the computed WQI atBaldi river upstream, Sahastradhara proper and downstream were 85.53, 83.48 and 82.30 during lockdownperiod (summer). However, during unlocking process (monsoon), due to continued weekend restrictions,on account of minimum tourists activities the water quality was still computed Good that NSF-WQI werefound to be 83.20, 80.58 and 79.27, at the studied locations respectively. |