2 weeks Ago
New Delhi: Delhi Jal Board said on Friday that construction of three wastewater treatment plants ( WWTP ) in Okhla in south Delhi, Kondli in east and Rithala in north Delhi was approaching completion. These facilities are part of Yamuna Action Plan-III , a river restoration initiative that seeks to reduce the quantity of untreated sewage entering the river. Officials have stated that all three projects would become operational soon.
The Okhla plant, which is touted to be Asia’s largest WWTP, is 96% complete. According to DJB, this plant will ensure treated water with at least a biological oxygen demand of 10 mg/l and total suspended solids of 10 mg/l. According to officials, the project will serve large parts of Delhi, including the South-Delhi area, treating the emanating wastewater.
“Around 56.4 crore litres of wastewater channelised from sewer networks will be treated or cleaned daily at this plant. It will benefit around 40 lakh residents in the capital,” said a DJB official.
DJB said that at Okhla ultraviolet technology has been employed for the first time in a WWTP to clean wastewater. “This technique is commonly used in reverse osmosis plants with the purpose of making the water potable/drinkable,” an official said. Another feature is the rectangular shape of the primary sedimentation unit instead of the usual circular pond.
Also, a lamella filter has been used in this section of the plant. Due to these changes, the time taken for the treatment of wastewater will be reduced to half, the official claimed. The rehabilitation and upgradation of Okhla WWTP began on June 19, 2019, but has seen several delays due to events like the Covid pandemic and the construction bans imposed due to excess air pollution in the winter months.
The Kondli Phase II project, to cater to east Delhi, especially Shahdara, is around 98% complete. “It is being developed with effluent standards of BOD 10 mg/l and TSS 10 mg/l or better with the objective of removing pollutants entering the Yamuna through wastewater,” said a DJB official. The project will prevent the outfall of wastewater into Yamuna without treatment.
The Rithala Phase 2 rehabilitation and upgradation project involves the development of a water unit that will cater to large parts of north and northwest Delhi. It will similarly disallow any untreated sewage from entering the Najafgarh Drain or the Yamuna. According to officials, a trial run has begun and the WWTP will be commissioned soon.
According to DJB, the reasons for the holdup in the completion of the projects were delays in getting clearances, anti-pollution construction bans and the Covid lockdown. But concerted efforts have resulted in these WWTPs nearing the finish line. “With these three mega WWTPs, we will try to ensure that the wastewater emanating from the households and industries of Delhi does not flow into the Yamuna untreated,” said the official.
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