Delhi govt plans study to identify pollution hotspots responsible for frothing in Yamuna

When water falls from a height at a barrage, the turbulence agitates the phosphoric compounds in the river which leads to the formation of froth, an official said.Experts say the problem of frothing will continue unless sewage treatment plants and common effluent treatment plants in Delhi are upgraded to meet the new standards and all unauthorised colonies are connected to the sewer network.Delhi generates around 770 MGD of wastewater.

The Delhi government will conduct a study to identify pollution hotspots, including colonies and industrial areas, responsible for frothing in the Yamuna river, officials have said.

The study also aims to form short and long-term action plans for minimizing foaming in the river, they said. According to the project proposal, the environment department's study will ascertain the sources and reasons behind the froth in the river which reflects the ''deadness of the water and nil (level of) dissolved oxygen in it''.

Frothing in certain stretches of the river, such as near ITO and the Okhla Barrage, has become an annual phenomenon in winters when the temperatures are low and flow in the river is less.

According to officials, the primary reason behind the formation of the toxic foam is the high phosphate content in the wastewater. Detergents used in dyeing industries, dhobi ghats, and households are the major sources of phosphate, they said.

''Wastewater from authorized colonies and settlements with high phosphate content reach the river through untapped drains. When water falls from a height at a barrage, the turbulence agitates the phosphoric compounds in the river which leads to the formation of froth,'' an official said.

Experts say the problem of frothing will continue unless sewage treatment plants and common effluent treatment plants in Delhi are upgraded to meet the new standards and all unauthorized colonies are connected to the sewer network.

Delhi generates around 770 MGD of wastewater. The 34 sewage treatment plants at 20 locations across Delhi treat up to 570 MGD of sewage. The rest empties into the river directly. Government data shows that only eight of the 34 operational sewage treatment plants in Delhi meet the prescribed standards for wastewater (BOD and TSS less than 10 mg per liter). Together, they can treat 150 million gallons of wastewater a day.

Sewer lines have been laid and commissioned in 716 of the 1,799 unauthorized colonies in the capital so far, government data showed. The study will identify major drains accounting for maximum pollution in the Yamuna river and hotspots, including colonies and industrial areas.

It will also assess and identify sources of froth in the Najafgarh drain and the supplementary drain, according to the proposal.

The 51-km Najafgarh drain is the largest in Delhi and it alone contributes around 60 percent of the total wastewater discharged from the capital into the Yamuna.

The study will also suggest possible alternatives to household products responsible for frothing.

In November last year, the city government had faced flak for having to deploy boats in the polluted river to remove toxic froth at Kalindi Kunj banks on the occasion of Chhath puja celebrations.

Authorities had even erected bamboo structures and sprayed water from tankers to dissipate the foam.

The criticism had prompted Chief Minister Arvind Kejriwal to announce a six-point action plan to clean the Delhi stretch of the river and constitute a Yamuna Cleaning Cell to improve coordination among the agencies involved in cleaning the heavily polluted river.

The chief minister had earlier promised to clean the river by 2025.

The 22-km stretch of the river between Wazirabad and Okhla, which is less than 2 percent of its 1,370-km span from Yamunotri to Allahabad, accounts for around 80 percent of the pollution load in the river.

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)