This is with reference to recent Media reports on the death of fishes at Jayanti Sarovar, Jubilee Park.
Some of the issues mentioned as likely causes of the incident like polluted water, dirty drainage systems, lack of cleanliness need to be answered in the correct perspective. In course of the normal routine work, JUSCO undertakes regular cleaning of lake embankments, it undertakes additional spraying of TOXIMAR medicine which helps stabilize oxygen levels in the water. In addition sprinkling of lime and potassium permanganate mixture is also done on a regular basis. 6 fountains are in operation for aeration purposes and 2 additional fountains will be installed by tomorrow. Finally, water is pumped when needed to improve water level. Hence, with regard to maintenance of water bodies, JUSCO has a installed system and the same is followed.
The recent media reports of death of fishes in unexpected high temperatures has been occuring in many places in this region. In the case of Jamshedpur, JUSCO has studied the issue which is essentially to do with decreased oxygen levels in a body of water. Most oxygen depletions occur in the summer months because warm water holds less dissolved oxygen than cool or cold water.
This decrease of oxygen levels occurs with sudden hot weather which can increase temperatures in the surface layer of water, as the warmer water tends to stay near the surface and be further heated by the air. In this case, the top warmer layer may have more oxygen than the lower, cooler layers because it has constant access to atmospheric oxygen. If a heavy wind or cold rain then occurs, the layers can mix. If the volume of low oxygen water is much greater than the volume in warm surface layer, this mixing can reduce oxygen levels throughout the water column and can lead to fish death. This is what happened yesterday.
Further, heavy rainfall often results in extensive surface runoff, which can carry large loads of municipal wastes, commercial wastes, market wastes, food wastes, garage wastes, etc. As a result it creates high Biochemical Oxygen Demand (BOD) which leads to low levels of oxygen in water column.
The recent cases of death of fishes is unfortunate and was possibly a fall out of an unexpected rise in temperature, a climatic condition over which no one has any control. However, it needs to be re-emphasised that JUSCO has total awareness of the issue and is taking steps to see that such incidences do not occur again.