CONSERVATION PLAN FOR KANKE LAKE

Abstract

Kanke Lake is located on the north-west corner of Ranchi city-the capital of Jharkhand state. The water of the lake is used only for the supply of drinking water to the city. It is a manmade lake with endorheic nature. River Pandra ends in the lake. The lake has small catchment with dendritic drainage pattern. Catchment has Granite-Gneiss soil structure and has dry semi-humid climate. Half of the catchment is densely populated portion of the Ranchi city. Anthropogenic interactions with lakes and its basin during the last few decades has been of concern largely due to the rapid population growth accompanied by intensified industrial, commercial and residential development that has led to the deterioration of the Kanke Lake ecosystem. The lake is facing threats like degradation of water quality, predominance of algae, shrinkage of carrying capacity of the lake due to sedimentation and decrease in biological diversity due to improper and in sufficient waste management, changes in land use pattern, lack of public awareness about the importance of the lake and nonparticipation of people in the affairs of the lake and absence of a strong and capable institution responsible for the lake. In this study, four aspects pertaining to the lake and its catchment viz, water quality and sediment analysis, waste management, public awareness and people's participation and institutional development were taken into consideration. Present status of these aspects has been studied in detail and gaps and issues have been identified. Some concrete suggestions along with recommendations have been made on each of these aspects. . The study indicates that there has been deterioration in the water quality of the lake with passing of time. Water quality parameters have gone a significant change. Present state of water quality underlines the immediate need of close monitoring and conservation and restoration measures. Sediment of the lake has high concentration of heavy metals like Cr, Pb, and Hg etc which is beyond the prescribed limit. Though the lake is mesotrophic but no thermal stratification takes place due to the agitation and movement of water layer at as a result of regular abstraction of water for treatment plant. Chlorophyll content in the water sample has been found very high which indicates the profuseness of algae in the water. iii Status of low cost sanitation has been found very poor around the lake and in its catchment. Open defecation and cattle grazing in the lake is prevalent. A big gap has been found in the existing capacity of sewage treatment and the volume of sewage generation. Need of solid waste management in scientific manner has been underlined. Proper suggestions and recommendations have been made. Status of public awareness regarding lake and their participation in the affairs of the lake has been found unsatisfactory. A plan for the same has been suggested. No single institution has been found responsible for, Kanke Lake. Hence, constitution of an authority with enough technical, financial and administrative strength with sufficient legal teeth has been suggested. After concluding the findings of the study, a comprehensive, cost-effective and feasible conservation plan has been suggested for the overall sustainable development of the whole environment of Kanke Lake. Present study could not cover the estimation of storm runoff, sediment transfer rate, water balance of the lake and biological trophic index which could have been more result oriented. Further study is needed to cover these topics. iv