NEW DELHI: In November last year, chief minister Arvind Kejriwal pledged to clean up the Yamuna by February 2025 and take a bath in the river. Since then, a few steps were taken in this direction, including allocation in the state budget for funds to restore the Najafgarh drain to its original status as the Sahibi river. However, daunting challenges remain, including high effluent load and low river water flow.
The city generates 3,491.4 million litres per day of sewage, but the sewage treatment plants only treat 2,477 MLD of this. A Delhi Pollution Control Committee report says that of the 30,000 plus industrial units in Delhi, 1,334 are water-polluting industrial units. But only discharge from 1,091 units are treated by 13 common effluent treatment plants. In addition, DPCC says of the 18 major drains in Delhi, five are untapped and flow directly into the Yamuna.
Not surprisingly, the condition of the river is almost the same as it was a few years ago.
In June 2021, the river Yamuna exited Delhi after a 22-km stretch with a biochemical oxygen demand count of 16mg/l against a norm of 1mg/l and faecal coliform count of 94,000 MPN/100ml against a safe standard of under 1. The readings had worsened in the latest analysis in May, with the river leaving the city with a BOD of 80 mg/l and FC count of 8,10,000 MPN/100ml. The dissolved oxygen level in both the years was nil, making the river virtually dead.
While Delhi government promised 100% sewerage and new STPs in the 2022-23 state budget, experts wonder if this will help when there is no water flow in the river. As Sushmita Sengupta, deputy programme manager (water), CSE, said, "Because many households in Delhi are still not connected with STPs, the faecal matter in the river is high. Moreover, there is no natural flow in the river, thus making it almost impossible to dilute the contamination. Whatever water can be procured is collected at Wazirabad and treated for drinking. So, there is no water in the Yamuna and what we see is sewage from the drains."
Sengupta pointed out how even when monsoon rain diluted the effluents, the Yamuna still "fails to achieve outdoor water standards".
Environmentalist Manoj Mishra too said there was no relationship between river and the sewer because both were separate systems. He said the treated sewage water could be an asset to be used for non-potable purposes, while the purity of the river depended on the flow. "If we rely only on STPs, then the deadline of a clean Yamuna by 2025 will move to 2050," said Mishra.
