Environmental pollution of Udaisagar lake and impact of phosphate mine, Udaipur, Rajasthan, India

 The study of water chemistry and sediment core samples from Udaisagar lake in Rajasthan has revealed high phosphate contents; 186 and 236 μg/l in surface and sub-surface waters and in core samples 0.157 wt % P₂O₅, low D.O. 4.61 and 3.50 mg/l on average in surface and depth waters and high E.C. 1316 and 1395 μs/cm and higher sedimentation rate 8.90 mm/year in this lake compared to other lakes in the vicinity. The enormous and wide-spread growth of algal bloom in lake water and Ahar river and occasional fish mortality are indications of eutrophic conditions prevailing in the lake. Such a situation is developing due to the discharge of pollutants from phosphorite mines, chemical factories, distillary, sewage and domestic waste from settlements, hotels throughout the length of River Ahar which during its journey receives and finally discharges pollution in this lake. This renders the water unhygenic for human consumption and deleterious to aquatic life. Received: 27 January 1998 · Accepted: 28 September 1998