Hydraulic and Hydrologic engineers work to prevent floods, to supply water for cities, industry and irrigation, to treat wastewater, to protect beaches, and to manage and redirect rivers. In the hydraulics and hydrology profession you will be using scientific study of the properties, distribution, and circulation of water on the surface of the land, in the soil and underlying rocks, and in the atmosphere.
In Civil Engineering's Hydraulic and Hydrologic Engineering specialty group, also sometimes termed Water Resources Engineering, you will deal with problems and issues involving the flow and storage of water. Specific applications have traditionally arisen in urban drainage, measures for mitigating the effects of floods and droughts, water supply, water treatment, and coastal protection. More recently, the flow implications for water quality have become of greater concern, and the transport of sediment, nutrients, and pollutants in natural or engineered watercourses has received greater attention. Research opportunities may be found in projects dealing with turbulent flows, watershed hydrology, environmental hydraulics, and contaminant transport.
For Complete lecture regarding FLOOD, click the link below
Engg. Hydrology NUST lecture
Feel free to write