New Delhi: Delhi this week witnessed its first ammonia spike episode in Yamuna in the new year leading to disruption in operations in two of its nine water treatment plants. On January 8, Delhi Jal Board (DJB), the capital’s water utility, issued an advisory stating that several parts of north, central and west Delhi are likely to face water supply shortages and supply at low pressure due to high levels of pollutants being received in Yamuna at Wazirabad pond. The water production at Wazirabad and Chandrawal water treatment plants was subsequently curtailed by 30-50%. The two Yamuna-fed plants supply around a quarter of the city’s 990 million gallons of water supply every day.
Ammonia spike episodes are not new to Delhi. A similar spike was reported on December 30. The scale of the problem of untreated industrial pollutants affecting city water supply can be gauged from the fact that the city annually witnesses 15 to 22 ammonia spike episodes spread over several days during which ammonia levels go above the 1 ppm level. The frequency of problems increases during winter, and December to March remains the worst affected period.
The source of water pollution in the Capital
A senior DJB official said that the source of industrial pollutants, indicated in terms of ammonia levels, lies upstream in Haryana as untreated industrial pollutants are released from the Panipat industrial area and Sonipat drains, falling into the Yamuna channel.
“Panipat drain 1 and drain 2 are the biggest sources of pollutants from dye industries. DD 8 and DD 6 drains are vulnerable points in Sonipat as Delhi’s fresh water and industrial waste run parallel in these drains which are separated by a few inch wide muddy wall,” the official added.
The pollutants come via wastewater and industrial wastewater discharged from Panipat drains, Rohtak X-regulator, DD-6 through DD-8 drain in Sonipat, which finally reaches Wazirabad barrage and in turn pollutes Yamuna downstream,” the official added.
The Haryana Pollution Control Board and Haryana Irrigation Department have repeatedly denied untreated industrial waste was being released in the drains. The interstate issue also became politically contentious around April-May 2021 as the city was facing the second devastating Covid wave when the Delhi government submitted to the apex court that low water supply may even hit the hospitals. The dispute has been taken to court multiple times, but no permanent solution has been found.
Water source
Delhi primarily relies on its neighbouring states for its water sources. Delhi gets around 40% of its water supply from Yamuna through the main river channel, CLC (Carrier Lined Canal) Munak canal and Delhi Sub-Branch (DSB) canal. In comparison, around 25% of water comes via the Upper Ganga canal (Gangnahar), 22% from Bhakra Nangal reservoir. In contrast, the rest of the water is derived from sub-surface resources such as Ranney wells and tubewells. The water supplied directly through the Yamuna channel is primarily impacted due to pollutants coming from upstream.
DJB’s plants can treat up to 0.9 ppm levels of ammonia in raw water, but chlorination beyond this limit produces toxic Chloramine compounds. “We try to divert water from other sources to dilute the raw water to keep the operations running. We plan to set up ozonation plants to increase the treatment capacity up to 4 ppm which may help us to deal with disruptions due to ammonia spikes,” a second official added.
Politics over pollution
The tussle between the AAP government and senior bureaucracy is also impacting the project of setting up an ammonia treatment plant. HT had reported on December 14 how the DJB plant treats high levels of ammonia in the Yamuna water, which was announced in March, will be delayed as the files about the project were yet to be cleared.
The plant was expected to be set up in four to five months. On December 28, water minister Atishi directed chief secretary Naresh Kumar to submit a report on the delay in setting up the ammonia treatment plant in Wazirabad. The minister attributed the problem to effluents released by Haryana and the non-maintenance of proper ecological flow in the river.
What experts say
Experts opine that while Delhi needs to expedite the much-delayed gradation of its water treatment plants, interstate agencies like CPCB and Upper Yamuna River Board need to intervene to curb the source of the pollution.
Diwan Singh, an environmental activist who led the ‘Yamuna Satyagraha’ for rejuvenating the river and other water bodies in the city, said that the problem has persisted for so many years and yet no resolution has been found. “We are required to work on technological upgrades of water treatment plants and tackling pollution sources. If the problem increases during the January to April period, patrolling of teams along the pollution sources and industrial areas along Yamuna should be increased in this time so that culprits can be caught,” he added.
Jyoti Sharma, head of Forum for Organised Resource Conservation and Enhancement (FORCE), a Delhi-based water conservation and sanitation organisation, said that regulations aren’t strictly enforced at the source of pollution. “We face similar water supply disruptions monthly due to pollution in Yamuna. Government channel monitoring is clearly not working. We need to make the people living near the drains which have outfall in Yamuna, stakeholders in the monitoring process. People should be empowered, and they should be able to raise red flags when drains carry industrial waste,” she added.