41 real-time monitoring stations to track Yamuna pollution by March

At present, Delhi does not have any system to monitor water quality in the Yamuna on a real-time basis. Instead, samples are collected once a month from eight locations on the river and from major drains, tested in laboratories, and published later on the Delhi Pollution Control Committee (DPCC) website

As the Yamuna continues to choke under sewage and industrial waste, Delhi is preparing to install 41 real-time online monitoring stations across the river and its major drains by March, a move that officials say will, for the first time, allow pollution spikes to be tracked as they happen.

The stations will measure flow, pH, biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), ammonium, dissolved oxygen, temperature and conductivity. (HT Archive)

The contract to set up 41 OLMS is likely to be awarded by the end of the month and the stations operationalised by March this year, officials aware of the matter said.

At present, Delhi does not have any system to monitor water quality in the Yamuna on a real-time basis. Instead, samples are collected once a month from eight locations on the river and from major drains, tested in laboratories, and published later on the Delhi Pollution Control Committee (DPCC) website, a process officials and experts say limits timely intervention.

The project, announced by the government in May last year, was recently approved by the DPCC in a board meeting and will provide real-time water quality data to the government, similar to the existing ambient air quality monitoring network.

Last May, the government had initially announced a plan to install 32 such stations, however, after failing to receive bids, a revised tender, for 41 stations, was floated in August. The tender stated that the project will also include five years of operation and maintenance, ensuring round-the-clock monitoring and transmission of data to the DPCC server.

This will include six location points in the river and 35 major drains, both in Delhi and NCR, which are connecting or bringing sewage into the river.

The stations will measure flow, pH, biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), ammonium, dissolved oxygen, temperature and conductivity.

“The project was recently approved by the DPCC in its board meeting. The tender will now be awarded by the end of the month. It will take an additional two months for these to be installed and operationalised, so it should be ready by March,” an official aware of the project said.

In 2018, the National Green Tribunal (NGT) appointed Yamuna monitoring committee (YMC) had said only a 2% stretch of the river in Delhi, stretching 22km, accounted for 76% of the total pollution load in the river.

Among the drains, the major contribution of wastewater – around 70% 00 comes from the Najafgarh drain, followed by around 16% from the Shahdara drain.

HT had on December 23 reported how data on water quality of the river Yamuna and of Delhi’s sewage treatment plants (STPs), common effluent treatment plants (CETPs) and drains, which are mandated to be collected at least once a month by the DPCC, had not been made available since October. The data was finally made available for November and December on January 11, after the National Green Tribunal in its December 22 order, asked DPCC to share Yamuna water quality data for the stretch from Wazirabad till Asgharpur.

The NGT in 2019 had earlier directed monthly data to be made available on the DPCC website, with a report available for every month since January 2013 for the Yamuna and from 2019 for Delhi’s drains, STPs and CETPs.

Experts said data transparency is crucial, noting that while existing records largely reflect monsoon conditions, comparative data from the lean season — from November onwards — is essential for informed decision-making. “Without adequate and timely data, there is no transparency. One cannot make decisions based on missing information or reports released only once a month,” said Bhim Singh Rawat, a Yamuna activist and member of the South Asia Network on Dams, Rivers and People (SANDRP).