Scouring is a phenomenon that is caused by the erosion of soil particles from the river bed. Basically, the scouring occurs when the erosion shear stress exceeds the critical shear stress. The size, shape, and density of sand particles, flow velocity, flow depth, turbulent intensity, and shape of scour holes influence the complex process of transportation and deposition of sediments. There are many types of scouring like local scouring, general scouring, contract scouring, abrasion scouring, degradation scouring, and lateral scouring. Previously many researches are done on local scouring such as identifying the scour depth and flow characteristics by using models, understanding the flow behavior by considering the flow conditions like waves and currents, determining the depth of scour with the use of empirical formula that depends upon parameters like diameter of particle (D), diameter of pile (b), hydraulic gradient (i), water depth (do), mean velocity of the undisturbed flow (v), critical velocity (v*), froude number (Nf). The empirical formulae are developed by considering flow parameters and geometrical parameters. Scour under wall jet is a phenomenon that occurs due to the difference in the flow velocity between the wall of the channel and the center of the channel. However, the scouring can be prevented by methods like protective mattresses, rock protection, and block mattresses. Further various research techniques are used to reduce the scouring near the hydraulic structures such as reducing the flow velocity of water, Riprap or Rock Armor, gabions, erosion control blankets/mats, and pile/sheet pile foundations. In this research, various previous literatures have been extensively studied on scouring which can be useful in designing the hydraulic structures.