Drainage ditches

Drainage ditches are a type of drainage system designed to remove or drain water from/into the surrounding soil. By reducing interstitial pressure, drainage ditches are able to stabilize a slope. Consequently, they are generally used to stabilize surface slips of a translational nature, which are quite frequent on slopes that are not particularly steep and have cohesive soil.

Drainage ditches are traditionally trenches dug out with a rectangular cross-section and filled with highly permeable natural inert material (gravel or quarried aggregate). Water can be carried along the ditch by means of the fill or using a drainage pipe laid in the base of the ditch.

To stop the drainage pipe becoming clogged, it is wrapped entirely in layers or nonwoven fabric.