Tarbela dam is one of the largest earth filled dam in the world used for power generation and irrigation purposes. Like all reservoirs the sediments inflow in the Tarbela reservoir has also resulted in reduction in water storage capacity and is also causing damage to the tunnels, the power generating units and ultimately to the plant equipment. This book is a starting effort in the modeling, simulation and analysis of Tarbela Dam infrastructure. Detailed simulation results highlight the critical areas for damage and ultimately the life prediction of the reservoir in terms of its storage capacity, erosion rate and strength of the tunnels. In first part of this book, results of numerical studies regarding water and sediment flow through Tarbela reservoir are discussed. In second part, results of numerical studies regarding turbulent flows through the tunnels with and without considering the effect of sediments, for different water heads, for one way and two way couplings, different injection techniques, different turbulence models are discussed. Numerical models developed will be helpful in the study of existing dams and the design of future projects.