Yamuna ammonia level spikes as water flows in from upstream states, Delhi blames Haryana

New Delhi

Heavy rainfall over the past week has led to a spike in ammonia levels of the Yamuna over the past three days, as evidenced by testing of raw water drawn from the river at Wazirabad, according to the Delhi Jal Board (DJB), which cited slush of industrial waste from upstream Haryana as the cause for the spike.

Officials said that initial monsoon spells carry the industrial waste accumulated in the drains of Haryana. Ammonia levels between 2 and 3 parts per million (ppm) were observed over the past three to four days, they said.

A senior DJB official said that the ammonia level reached over 3ppm on Thursday, following the first increased water flow. “Pollutants are getting diluted progressively and the level is currently at around 1.3ppm,” the official, not wanting to be named, said.

DJB can treat up to 0.9 ppm of ammonia level in raw water, but beyond such a high level, neutralisation of ammonia with chlorine gas regularly leads to toxic chloramine compounds.

Reports of the DJB show that the water utility supplied 938 MGD (million gallons a day) water against a target of 1,000 MGD on July 4, as the production was impacted at both Chandrawal and Wazirabad water treatment plants due to high ammonia levels. On July 5, the water supply level dipped further, to 934 MGD, and recovered to 972 MGD on July 6. High ammonia levels are indicators of industrial waste and dyes in raw water.

DJB officials said that the pollutants, such as dyes, chlorides and ammonia-based chemicals, flow from the Panipat industrial dye drain. “We can treat other impurities, but not ammonia beyond 0.9 ppm. With the drains flowing at full capacity due to rainfall in upstream states, pollutants accumulated at the base of drains get flushed out. The situation is now slowly heading towards normalcy,” the official cited above said.

Besides Panipat, DJB also cited the intermixing of industrial waste in Sonepat, where two canals carrying freshwater and industrial water run parallel to each other, separated by a sand wall of a few inches.

Haryana has maintained that there are no leaking pollution sources in its industrial areas.

On July 5, HT reported that images of dead fish floating in the Yamuna surfaced over the last few days, which is an indicator of low BOD (biological oxygen demand) and DO (dissolved oxygen). Locals said dead fish began showing up along the river floodplain almost a fortnight ago, with the situation improving in the last few days.

Faiyaz Khudsar, scientist in charge of DDA’s biodiversity parks programme, said a drop in oxygen in the river generally occurs when the river receives a large quantity of sewage and effluents. “For the dissolved oxygen to improve, a lot of water needs to be released from Hathanikund, which washes away the pollutants. After rains began last week, the DO has started improving gradually,” Khudsar said.

The problem of high ammonia levels in raw water is witnessed throughout the year, but the frequency of ammonia spikes recorded in winter (between January and March) is relatively higher, with the city witnessing 15-20 such episodes every year. Over the past few years, DJB has repeatedly announced that it will install advanced ozonation and in situ treatment plants at water treatment facilities to increase ammonia treatment capacity, but the project remains a work in progress.