The Delhi Pollution Control Committee (DPCC) has revealed a stark deterioration in the Yamuna River’s health as it traverses Delhi.
According to the June data, the biological oxygen demand (BOD) levels surged from a manageable 2mg/litre at Palla, where the river enters Delhi, to a concerning 85mg/l at Asgarpur, where it exits. This alarming increase indicates severe pollution, with BOD levels exceeding the permissible limit of 3mg/l by nearly 28 times at Asgarpur.
BOD is a critical indicator of water quality, reflecting the amount of oxygen required by aquatic life and organisms in the river. Higher BOD levels denote higher pollution, making it increasingly difficult for aquatic life to survive. As the Yamuna flows downstream, its BOD levels demonstrate a troubling trend. While the BOD at Palla was within acceptable limits, it escalated to 7mg/l at Wazirabad, 47mg/l at Kashmere Gate, 30mg/l at the ITO bridge, 40mg/l at Nizamuddin bridge, and 50mg/l at Okhla Barrage, before peaking at 85mg/l at Asgarpur.
The primary culprit for this drastic increase is the influx of sewage and industrial effluents, particularly after the confluence of the Shahdara and Tughlaqabad drains at Asgarpur. The situation has worsened compared to last June when the highest recorded BOD was 50mg/l at the same site. The May report also mirrored this worrying trend, with BOD levels reaching up to 75mg/l.
The Yamuna’s water quality saw temporary improvement last year due to an unusually heavy monsoon, which caused the river to swell beyond the danger mark, effectively diluting the pollutants. However, the samples collected by the DPCC on June 3 this year, during a severe heatwave and water crisis in Delhi, paint a grim picture. The lower flow of the river, exacerbated by a dry May and June, has contributed to the higher concentration of pollutants.
Environmental experts emphasise that the core issue remains unaddressed: the continuous discharge of untreated sewage into the Yamuna. “Until sewage inflow into the Yamuna is halted, any improvement in water quality will be superficial and temporary, largely dependent on the river’s environmental flow,” one activist noted. They highlighted that during the monsoon, when Haryana releases more water, there is a transient improvement in water quality, but this is not due to any substantial remedial actions by the government.
Another expert criticised the reliance on increased water flow for temporary respite, stating, “The Yamuna has essentially become a drain, with its water quality improvements hinging solely on increased flow rather than effective pollution control measures.”
