In-depth information about the concepts of hydrodynamics and natural water sources has been described in this all-inclusive book. Information regarding the properties of fluids and their capability to transport materials and physical features is extremely significant. The quantification of the activity of fluids is a complicated task. This complexity is demonstrated primarily when natural flows occurring in large scales (rivers, lakes, oceans) are considered. This book discusses various features of flows in natural water bodies, like the evolution of plumes, the transport of sediments, air-water mixtures, etc. The major topics covered in the book include tidal and wave dynamics of various water bodies, and multiphase phenomena such as air-water flows and sediments. The book provides conceptual arguments, experimental and numerical results, and demonstrates practical functions of the procedures and tools of hydrodynamics.