Appraisal of water quality of Rewalsar Lake during Baisakhi fair (harvest festival) in Himachal Pradesh, India

The purpose of the work was to study water quality of Rewalsar Lake with respect to physico-chemical parameters especially during baisakhi fair (harvest festival) in Himachal Pradesh, India. Results have shown slight alkaline nature of water with high dissolved solids and low visibility. High calcium (55 mg/L), sodium (29 mg/L), chloride (16.80 mg/L) and potassium (22 mg/L) were also observed during fair, however overall mean value were (41.60±1.89 mg/L), (17.66±2.02 mg/L), (10.27±0.87 mg/L) and (16.18±0.95 mg/L) respectively. Phosphate (21 mg/L), sulphate (55 mg/L), chemical oxygen demand (COD) (125 mg/L), biological oxygen demand (BOD) (48 mg/L) were recorded with overall mean values of (16.36±0.83 mg/L), (40.17±2.06 mg/L), (83.08±6.26 mg/L) and (33.33±2.20 mg/L) respectively. Significant high concentrations of BOD and COD showed that lake water is unfit for human and animal consumption. Maximum values of each parameter during baisakhi fair showed presence of organic and inorganic pollutants in lake water. Thus, the present study revealed that lake touched the critical stage of water pollution especially during baisakhi fair due to massive anthropogenic pressure. Proper conservation, management plans, strategies have to be formulated by government for restoration and rejuvenation of religious lake.