Check dams, or gully plugs, are structures built across channels to reduce erosion, by lowering water speed and accumulating sediments during floods.
They are often introduced in already degraded areas, where natural or agricultural vegetation cover was lost or not capable of holding the top soil.
Usually they are built in areas hit by intense runoff events, where conventional erosion control techniques are not sufficient.
Check dams need to be built at the right places, ideally where water can be directed to suitable areas for groundwater recharge.
In addition, work needs to be started in the upstream of a catchment in order to avoid destruction of the structures.
Due to their relative simplicity and easy implementation, they represent one of the most used stabilisation measures worldwide.