Landslide prevention using drainage trenches lined with fast growing trees.
Type: Technologies
Creation: 2011-04-30 08:51 Updated: 2021-11-02 15:23
Compilers: Giuseppe Bonati
Reviewers: Alexandra Gavilano, David Streiff, Joana Eichenberger
Country/ region/ locations where the Technology has been applied and which are covered by this assessment
- Country: Tajikistan
- Region/ State/ Province: Khatlon
- Further specification of location (e.g. municipality, town, etc.), if relevant: Khovaling
- Map: View Map
Description of the SLM Technology
Short description of the Technology
The construction of linear gravel bed ditches lined with local tree species, at angles across a hill slope to channel the surface water.
Detailed description of the Technology
A series of 80m long ditches are constructed at angles of approximately 30 degrees, across a hill slope at the base of the watershed. This land is prone to waterlogging, therefore several ditches approximately 0.5m deep, with a gravel bed to prevent erosion, drain the excess surface water away to the main tributary of the watershed. The edge of the ditches are further lined with fast growing tree species such as willow and poplar for stabilisation and afforestation purposes.
Purpose of the Technology: The purpose of the ditches is two fold, firstly to channel the surface water to prevent waterlogging that had previously led to landslides and small mud flows. Secondly, to enable cultivation on land that was previously unusable.
Establishment / maintenance activities and inputs: The technology is very simple and cost effective. Initially there needs to be an assessment of the amount of surface water that runs over the slope, this will determine the number of ditches required. The ditches are marked out, running at approximately 30 degrees perpendicular to the slope. The ditches are dug to a depth of 0.5m (or deeper) and filled with a base layer of stone to prevent the bed of the ditch from being eroded. Once the ditch is established, preferably in the spring time, fast growing and naturally available cuttings from trees such as poplars and willows are planted alongside the edge of the ditch at 0.2m intervals. These will stabilise the ditch bank and as the trees become established some thinning out will be required due to their close proximity to each other.
Natural / human environment: The area used is a hillside slope, subject to substantial amounts of surface water run off due to its location at the base of the watershed. The region suffers from a lack of accessible irrigation water, especially during the hot summer months. This technology allows land to be brought into cultivation that has natural access to water and is able to sustain vegetation during the dry months.
Photos of the Technology
- 📍 JONBAKHT, KHOVALING
- 📷 BONATI GIUSEPPE (C/O CESVI TAJIKISTAN)
- 📍 JONBAKHT, KHOVALING
- 📷 Foteh Rahmatilloev (CESVI TAJIKISTAN)