Varanasi is a religious city of India, popularly known for its mythological ponds. But, due to modern developments and urbanisation, the ponds of this city are struggling for their existence. In spite of the global alarm for restoration of the water bodies, the ponds in this city are facing neglectance. As apart of our study, the popular Sarang pond in the city was selected by us for detailed investigation. Physico-chemical analysis of water of the pond was conducted fortnightly, for selected parameters. For convenience, the data were expressed seasonally. In the present paper the data collected during summer of year 2007 has been discussed.
Average
temperature of the water was found to be 31 degree Celsius. The value of
total alkalinity was found to be 80 ppm, however,
pH of the water was 7.95 .
D.O.,
B.O.D. and
C.O.D. of the water of the pond was found to be 1.6 mg/L, 2.7 ppm and 13.5 ppm respectively, at the same time
D.O. after dilution was only3.3 mg/L. This is self explanatory for the level of pollution of the pond. Electrical Conductivity (
E.C.) was 1.314 mho/cm, while Total Hardness (
T.H.) was evaluated to be 463.3 ppm.
Chloride in the water was found to be 90 ppm and Total Dissolved Solids (
T. D.S.) was 1200mg/L, these values were much beyond the permissible limit.
The water samples were also analysed for the presence of
Calcium,
Phosphate and
Nitrate which were recorded to be 64.8, 1.6 and 30 ppm respectively. Reason for higher value of these parameters was contributed to the directly falling liquid waste from the adjoining residential apartments. The mean value of
Oil and Grease was found to be 0.2g/L, though; no prominent source for Oil and Grease in the pond was noticed, other than the kitchen waste. On the basis of the results of the analysis, the pond was marked as a highly polluted water body.
Prominent sources for its pollution were the domestic sewage, kitchen flow and the street runoff. In addition, solid waste and garbage tied in polyethene bags were recorded along its bank and also floating in the water surface.
Though, it appears surprising, but it is a fact that
this pond has been the only source for drinking water for the locals, according to the history.