Hydropower is defined as the power harnessed from the energy of running or falling water. It is a well-known fact that hydroelectric energy is the world's most common and vastly utilized inexhaustible energy form, and that it comprises of 16% of the global electricity consumption. This book basically talks about the theoretical and exercised solutions arrived at by the authors after years of hard work in experiments, considering the issues in the structure and functioning of a considerable number of hydroelectric power plants in different countries. The book has been edited with a view that it can serve as a textbook to students learning hydro power plants. The topics of the book are varied including the basic elements of hydro power plants, from the upstream end, with the basin for water incorporation, to the downstream end of the water flow outlet.