Lucknow (Uttar Pradesh): The Uttar Pradesh Pollution Control Board (UPPCB) data shows that the pollution level in the Yamuna has worsened this year. The Yamuna enters Noida with no dissolved oxygen in it and exits in the city even with higher level of pollution.
The UPPCB report does not mention the data for industrial effluents like quantity of hard metals -- mercury, arsenic, lead, etc -- the state pollution body has tested water on basic parameters -- dissolved oxygen (DO) and biochemical oxygen demand (BOD) -- and found the pollution levels very high. According to the data, in May 2021, the dissolved oxygen (DO) level of Yamuna was nil at Okhla barrage, the entry point of the river.
The minimum requirement of DO is 4 mg/l for category D (propagation of aquatic life) water and 6 mg/l for category A (drinking). As per the UPPCB report, Noida is the only city in Uttar Pradesh where the Yamuna falls under 'E' category, that makes the river unfit for drinking even after conventional treatment and disinfection, bathing or survival of fish and other aquatic organisms.
Read: Rising pollution in Yamuna leads to 40% decline in Delhi's water supply