This book is divided into two main chapters physico-chemical properties and biological characteristics of fresh water lake (Kunigal). The environmental science is fast emerging interdisciplinary branch of science which has already acquired significant portions in basic research of applied sciences. Physico-chemical properties and biological characteristics of water is one of the important aspects of environmental science which desires a greater emphasis because of its widespread nature. Environmental programme that focuses on the application of biological, chemical, and physical principles to the study of the physical environment and the solution of environmental problems, including subjects such as abating or controlling environmental pollution and degradation; the interaction between human society and the natural environment; and natural resources management. I did feel the need of a book which could provide comprehensive information on physical, chemical and biological characteristics regarding their sources, effects and control of fresh water lake particularly Kunigal.