close_game
close_game

Only 2 of 18 drains in Delhi pass crucial test

Aug 17, 2023 11:54 PM IST

The Shahdara drain emerged as Delhi’s most polluting drain this August, recording a BOD concentration of 53 mg/litre

Only two of the 18 major drains in Delhi met the biological oxygen demand (BOD) standard of 30mg/litre or less in the month of August, the latest water analysis report released by the Delhi Pollution Control Committee (DPCC) showed, indicating that considerable efforts are still required to control sewage and industrial effluents flowing through these drains into the Yamuna.

The report said that considerable efforts are still required to control sewage and industrial effluents flowing through these drains into the Yamuna. (Sunil Ghosh/HT Photo)
The report said that considerable efforts are still required to control sewage and industrial effluents flowing through these drains into the Yamuna. (Sunil Ghosh/HT Photo)

The Shahdara drain emerged as Delhi’s most polluting drain this August, recording a BOD concentration of 53 mg/litre. The BOD concentration in the drain was 58 mg/litre in the last sample collection report from June, which indicated slight progress. DPCC was unable to collect samples from the drains in July, owing to the floods in Delhi.

However, the pollution level in the Najafgarh drain — Delhi’s largest accounting for nearly 69% of all pollution in the Yamuna — was at its lowest since February 2021, the data showed. Najafgarh drain’s BOD this month was 42 mg/litre, which, while being above 30 mg/litre was still the lowest reading for the drain since February 2021. It was 35 mg/litre in February 2021.

The two drains which met the BOD standards were the Metcalf House drain (28mg/litre) and the Khyber Pass drain (30mg/litre)

DPCC monitored a total of 23 drains and collected samples on August 3, the report dated August 11 showed.

BOD is considered an indicator of how polluted the water is in a river or a drain. It represents the amount of oxygen used up when organic matter, such as sewage, is broken down, thus representing the quantity of pollutants. When high levels of oxygen are used up in the breakdown of pollutants, the dissolved oxygen for the survival of aquatic life reduces. The 30mg/l or lower BOD standard for drains has been set by the Central Pollution Control Board (CPCB).

Najafgarh drain’s BOD concentration was 50 mg/litre in June, 48 mg/litre in May, and 60 mg/litre in April, while last August, it was 75 mg/litre.

The body has been collecting monthly data on drains for Delhi since July 2019, following directions from the National Green Tribunal to monitor total suspended solids (TSS), chemical oxygen demand (COD), and PH levels, in addition to BOD.

Data shared by the environment department with the National Green Tribunal-appointed high-level committee on the Yamuna in January identified that the Najafgarh drain accounts for 68.71% of wastewater being discharged into the Yamuna, followed by the Shahdara drain (10.9%) and the Barapullah drain (3.15%).

Delhi’s 18 major drains that end up in the Yamuna include the Magazine Road drain, Sweeper Colony drain, Khyber Pass drain, Metcalf House drain, Tonga Stand drain, Moat drain, Civil-Military drain, Delhi Gate drain, drain number 14, Tughlakabad drain, Kalkaji drain, Tehkhand drain, Sen Nursing Home drain (drain 12), Shahdara drain, Najafgarh drain, Mori Gate drain, Barapullah drain, and the Maharani Bagh drain.

Among these, 11 drains in Delhi have been trapped completely, according to a report submitted by the environment department to the HLC in March. The report also said that two drains were partially trapped — at Delhi Gate and Sen Nursing Home.

Five drains are yet to be trapped, including the drains at Najafgarh, Shahdara, Barapullah, Maharani Bagh, and Mori Gate.

The environment department and the Delhi Jal Board (DJB) said that both Najafgarh and Shahdara drains were too large to be trapped and that only their supplementary drains could be trapped and connected to Sewage Treatment Plants (STP). The remaining three drains are to be trapped by September 2023.

Experts said that unless all drains are trapped regularly, sewage will continue to enter the river.

“Delhi is likely helped by rain, which can dilute TSS and reduce the BOD too. We saw good rain in July and eventually floods. In the first few days in August too, spells of rain were recorded in Delhi. Until most drains meet the BOD standard regularly, sewage will eventually the Yamuna,” Bhim Singh Rawat, a Yamuna activist and member of the South Asia Network on Dams, Rivers and People (SANDRP).

rec-icon Recommended Topics
Share this article
Catch every big hit, every wicket with Crickit, a one stop destination for Live Scores, Match Stats, Infographics & much more. Explore now!

Stay updated with all top Cities including, Bengaluru, Delhi, Mumbai and more across India. Stay informed on the latest happenings in World News along with Delhi Election 2025 and Delhi Election Result 2025 Live, New Delhi Election Result Live, Kalkaji Election Result Live at Hindustan Times.
See More
Catch every big hit, every wicket with Crickit, a one stop destination for Live Scores, Match Stats, Infographics & much more. Explore now!

Stay updated with all top Cities including, Bengaluru, Delhi, Mumbai and more across India. Stay informed on the latest happenings in World News along with Delhi Election 2025 and Delhi Election Result 2025 Live, New Delhi Election Result Live, Kalkaji Election Result Live at Hindustan Times.
SHARE THIS ARTICLE ON
SHARE
Story Saved
Live Score
Saved Articles
Following
My Reads
Sign out
New Delhi 0C
Tuesday, February 18, 2025
Start 14 Days Free Trial Subscribe Now
Follow Us On