“Before declaring a war, learn thoroughly about the enemy being fought.”
As stated earlier, Yamuna is relatively cleaner before entering Delhi but as it proceeds into the city, its water quality consistently deteriorates. As the river moves out of the national capital, its water is unfit for any use. Astonishment lies in the fact that only 26 km of downstream into Delhi is responsible for more than 70% of pollution the river suffers from.
Yamuna basin is stretched for 48 km in the NCR. In the length of 26 km between Wazirabad and Okhla barrages, more than 28 small and gigantic drains discharge their waste water into the river. Some drains like Najafgarh, Tughlaqabad, Barapullah, Ghazipur and Western Yamuna Canal are considerably proportionate to the volume of Yamuna water. Due to high water demand of the metropolis, very less riverwater is released from the Wazirabad barrage. Hence, most of Delhi’s yamuna water comes from these drains. Reportedly, more than 95% of the pollutants in Yamuna come from these drains.
More than 748 million Gallons sewage is generated in Delhi per day and 32 functional STPs treat around only 490 MGD. More than 30% of the waste generated gets dumped in the river untreated.
Why were these drains created?
With such a fatal harm these drains cause to the river, one might wonder why were these even created? These are actually seasonal storm water drains which were earlier used to translate rainwater for optimum utilisation. Moreover, these drains diverted water into river Yamuna during downpours to prevent flooding in the whole city.
A report from IIT Delhi states that till 1976, 201 natural drains were present in Delhi but by 2018, 19 of them disappeared and rest were converted into sewers.
Where do these pollutants come from?
More than 46% that accounts for 6.5 million of Delhi’s population lacks an adequate waste disposal system. Thus, these households dump contaminants directly or indirectly to these drains. As per NGT report,2017 more than 58% of the household waste reaches Yamuna untreated. Major contributors of pollution from households are grey water, blackwater(faecal water), soaps &detergents, paper and plastic. As per the current statistics, household waste is the biggest contributor in the river’s pollution.
Second in line are the industries of the urban city. Industries also have a major influence in the river’s retarding health. According to YMC report, a total of 910 units of industries connected to these drains were recognised to contaminate the river with pollutants like grease, acids, oil, plastic and other toxic chemicals. The report further stated that 28 industrial clusters are present in Delhi out of which only 17 are connected to 13 common effluent treatment plants (CETP). The remaining 11 clusters are not connected to any such plants.This report highlighted that 22 industrial units are directly releasing the produced junk into the stream. Most of such industries were located in Okhla industrial area. These industries include paper, metal finishing units, chemical units, distillery, pharmaceuticals, textile industries and thermal power stations.
Rather less worked on but a major undetected problem is agricultural runoffs. Practicing unskillful farming near the banks of river Yamuna, some farmers use chemicals like pesticides, fertilisers, urea and DDT inadequatly for cropping. Percolation of toxic water from these fields remarkably alter the composition of nutrients in the river.The most commonly known type of pollutants are the religious oblations. The river throughout its course receives heavy religious offerings such as residues of pyres, flowers, sculptural statues, plastic etc. These offerings are an additional reason of trouble to the already befouled river.Every adulterant in its share, contaminates the river. The concern lies not in the production of these pollutants but in their coalescence with the river. What appears to be a river while entering Delhi comes out as a gigantic sewer which no treatment can make fit for utilisation. The only way to keep the river clean is by minimising the impurities blending into it.
In the next article we shall depict the nature of these impurities and the damage they’ve caused to the river.