Over the years, unchecked soil erosion can lead to the formation of deeper and deeper gullies. There are several methods for controlling gully erosion, which can be chosen depending on the materials available.
If it is a small gully, vegetation can be planted in strips across the gully to slow the velocity of water, trap silt, and prevent further erosion.
Brush check dams can be built across the gully by driving wooden pegs into the ground and then intertwining bush-wood along the pegs. Silt will be trapped behind the dam
Dams can also be constructed using loose boulders. To prevent erosion under the boulders, they should be filled in 0.3 meters beneath the level of the gully bed, and the stones should form a gradual slope to the downstream side of the dam (see picture).
In areas with high slope and rainfall, a stronger structure may be necessary. Gabions are wire woven baskets filled with stones, and can be placed across the gully as shown in the picture.
Loose Boulder Check Dam