The carcass of a 10kg rohu floats in Jayanti Sarovar on Monday. Picture by Bhola Prasad
Hundreds of fish, their mouths open, floated up the surface of Jamshedpur’s landmark Jayanti Sarovar in Jubilee Park early Monday morning, dead apparently due to depleting oxygen and sudden inflow of water packed with toxins.
Anglers and members of Jamshedpur Angling Club (JAC) estimated around 200 fish, mostly rohu, katla and catfish, weighing anywhere between 1.5kg and 25kg, were the day’s casualties.
The Telegraph, in its report Not all green’s good, discovers showpiece lake (April 23), indicated the threat to fish due to dense algae and aquatic plants and shrinking water level. Since May 2, Friday, Nor’wester showers caused polluted groundwater to flow into the lake through inlets, worsening the situation.
Jusco workers removed dead fish in the morning and buried them at the dump yard near Marine Drive.
K.K. Sharma, Jamshedpur Cooperative College zoology department head and Ornithological Society of India (Bihar-Jharkhand) member, told The Telegraph that fish fatalities occurred due to these twin causes acting together.
“This lake is getting shallower due to silt and gravel accumulation, while algae has covered large tracts. Together, these have reduced oxygen content and suffocated the fish. Then, the Nor’wester showers caused sludgy water to gush into the lake. The fish, already grappling with less oxygen, could not survive the sudden onslaught of toxins and sudden change in temperature,” Sharma said.
The shallow part of the lake, which used to be 4-5 feet deep formerly, is now only 2 feet low. Its flanks, barely a foot deep, can be easily seen. Algae and weeds use up dissolved oxygen in the already shallow water. Fish can’t breathe if oxygen in water gets less than 4PPM (parts per million).
In the past few days, dissolved oxygen levels dipped further as toxic water, pushed along by Nor’wester rains, gushed into the lake from two inlets near the ends of Old Court (close to laser fountain show) and Tata Steel zoo.
Jamshedpur Angling Club secretary Geoffrey Bonjour said they sprayed Toximar, a medicine that neutralises pollutants in water, on Sunday evening. “We sprayed 20kg medicine on the lake. But it was apparently too little too late, because the quantity was effective for only one acre of the 10-acre lake and it was a task we should have undertaken earlier. Polluted water from inlets had been gushing to the lake from last Friday after Nor’wester showers,” he said.
Spokesperson of lake’s civic guardian Jusco, Rajesh Rajan admitted fish deaths occurred due to toxic water entering the lake from the inlets.
“Polluted water from city areas entered the lake through inlets. We are testing water samples collected from near inlets at our lab to find out exact contents. We are also planning remedial measures such as a pit near the inlet so that solid wastes do not gush into lake through accumulated rainwater,” Rajan said.
East Singhbhum district fisheries officer Arun Kumar, when contacted, said he was surprised Jusco had not followed standard operating protocols such as spraying potassium permanganate and lime in the reservoir during “extreme heat conditions”, especially when the water level was so low.
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