|Special Public Works Programmes - SPWP - Anti-Erosion Ditches - Training Element and Technical Guide for SPWP Workers, Booklet No. 1 (ILO - UNDP, 84 p.)|
|3. Different types of anti-erosion ditches|
The purpose of this type of ditch is to stop the flow of overland run-off water and allow it to be absorbed by the soil; in addition, the sediment carried by the water is collected by the pit.
These are protective structures which are located uphill from cultivated land.
They are rectangular sections, 40 cm wide, 20 cm deep and between 3 to 25 m in length and are dug along the contour line with 2 m of levelling between each ditch.
The ditches are blocked off in a zigzag pattern by a mound of earth 50-100 cm wide every 3 to 25 m to provide a path for men and animals.
SILT CATCHMENT PITS