Last eight years, the dissolved oxygen reached the threshold 4mg/l

Hussainsagar is dead. Rather, it cannot support any aquatic life. A recent Telangana State Pollution Control Board analysis of its waters revealed that the lake has no dissolved oxygen.“For any water body to sustain life, it should have dissolved oxygen of 4 mg or more. We recorded zero findings in all the seven locations from where water samples were collected and analysed,” says P. Veeranna, Joint Chief Environmental Scientist, who carried out the tests.Officials of the department collected samples from seven locations where water enters or exits the lake and subjected it to a battery of tests. Over the last eight years, the dissolved oxygen reached the threshold 4mg/l only in 2011 and 2015.

The other parameters of pollution in Hussainsagar are also off the charts, according to the water analysis. The water meets the lowest standard of category ‘E’ of Central Pollution Control Board’s ‘Irrigation, industrial cooling, controlled waste disposal’ requirement. The samples barely made it to E category due to lower electrical conductivity than the benchmark parameter of 2250 µs/cm. “Higher electrical conductivity indicates higher presence of metal ions in water. A higher number will lead to a situation where reverse osmosis will take place, draining fluids from aquatic life,” informs Mr. Veeranna.At the two inlet channels of Sanjeevaiah Park and Necklace Road, the total coliform count was 5850 Most Probable Number/per 100ml and 5800 MPN/100ml respectively. Coliform is a rod shaped bacteria that occurs in human and animal waste, and is considered dangerous to human health.

Dug in 1565 on orders of Qutb Shahi king Ibrahim Qutb Shah, Hussainsagar was a source of water for decades and sprawled over 6 sqkm or 1,468 acres. Now, officials estimate its expanse to be 4.7 sqkm or 1,161 acres.“My office is on the other side of Hussainsagar. The smell is intolerable. Sometimes even breathing becomes difficult,” says IPS officer Tejdeep Kaur Menon, whose office is located at Buddha Bhavan near an outlet of the lake.

Restaurants abutting Hussainsagar are also victims of the foul smell emanating from the lake. The stench is so high that restaurants on Eat Street have fewer visitors even during summer. “Some couples keep coming and spending time here, but families have stopped coming. On some days, even standing by the lake is difficult due to the odour,” says Bharat, who runs a chocolate outlet in the recreation space.The water analysis spotlights the functioning of multiple Sewage Treatment Plants.

The toxic Hussainsagar is also having a cascading effect downstream where the water is let out. If Musi at Gandipet has Biological Oxygen Demand at 3mg/l at Nagole, after the Hussainsagar water mixes with it, the BOD spikes to 39 mg/l.