Stabilised and reinforced soil using vetiver
A plant with deep roots (3-4 m) that helps to combat soil erosion and stabilise road embankment.
This solution received the Caisse des Dépôts 2013 Innovation and Sustainable Development award. Used successfully in Brazzaville (Congo), it has helped to avoid the use of heavier and more expensive construction materials that would have had an impact on the landscape, as well as contributing to improving the living conditions of inhabitants.
Closely planted, vetiver grows in dense hedges that reduce water speed on the soil surface, and encourage infiltration. Its deep roots (3-4 m) give it good anchorage even in unstable soils. Vetiver can therefore withstand winds and sandstorms. This morphology means that slopes can be stabilised by stopping or slowing down erosion.
Soil erosion, exacerbated by climate change, is a threat to infrastructure of all kinds, including homes and consequently the population. The use of vetiver, a locally grown plant, avoids the use of heavier and more expensive construction materials that would have had an impact on the landscape, as well as contributing to improving the living conditions of local people.
Benefits: including vetiver in more conventional anti-erosion solutions (gabion walls, concrete, drainage, earthworks, etc.) allows us to:
- optimise implementation and reduce costs (more than 13 times cheaper than solutions such as gabion or concrete walls); vetiver requires very little water (irrigation)
- maintain local homes
- develop local employment (an initiative that requires intensive local labour. It provides jobs in nurseries, on work sites and in maintenance)
- improve the living environment through a green canopy.
- enrich the soil (increases fertility)
- absorb and sequester carbon from the atmosphere
- fight against insects and other pests (e.g. termites)
- build a habitat for flora and fauna
- use local resources (vetiver is grown for its essential oil)
For more information, see the leaflet ” Vetiver grass: an innovative technique for soil stabilisation”