Soil erosion takes place when the shear force generated due to the external agencies such as wind and flowing water exceeds the shearing resistance of the soil particles. To control soil erosion, the shear resistance has to be increased Due to erosion, the banks of rivers may cut into the natural ground and road or railway embankments may collapse, leading to serious catastrophes. In case of agricultural soils, the top layer of soil may become depleted and lead to the loss of fertile soil. It is reported that the soil is swept and washed faster than natural replenishment ten times in USA and thirty to forty times faster in China and India.
Erosion can be controlled by different methods as natural vegetation, turfing, rip-rap, stone pitching, mats, groynes , and gabions.