Present study points out the impact of Lockdown on the health of the Yamuna river at Delhi stretch by comparing prelockdown and Post-lockdown period by studying the reports of pollution monitoring agencies. Delhi segment of the Yamuna is highly polluted, where alongwith domestic sewage a huge quantity of industrial waste is being discharged continuously without proper treatment. Pre lockdown (March 2020) water quality parameters at three sampling stations named as Palla, Nizammuddin Bridge and Okhla barrage U/s in Delhi were, pH were 8.7, 7.3 and 7.2, DO were 17.1 mg/L, not detected in later two sites, BOD were 7.9 mg/L, 57 mg/L and 27 mg/L and COD were 28 mg/L, 90 mg/L and 95 mg/L respectively and postlockdown period (April 2020) the pH was 7.8, 7.2 and 7.1, DO was 8.3 mg/L, 2.4 mg/L and 1.2 mg/L BOD was 2 mg/L, 5.6 mg/ L and 6.1 mg/L and COD were 6 mg/L, 16 mg/L and 18 mg/L respectively. The study of these parameters at three sampling stations reveals that the lack of industrial pollutants discharging due to nationwide lockdown for COVID-19 pandemic had positive effect on water quality of this river. Water quality could be maintained by planned establishment of industries and setup of ETP with without gap between generation and treatment.
Roles of Lanthanum and Cerium in Grain Refinement of Steels during Solidification
