Ecological applications for flood hazard minimization in the Siwaliks region of Nepal

Abstract:

Water-induced disaster problems including soil erosion, debris flow, landslides and flooding are common due to the unstable landscape of Siwaliks region of Nepal. Ecological applications especially focused on soil bioengineering techniques have been used in Nepal for nearly four decades to deal with erosion problems on slopes, in high way construction and riverbank stabilization. In this study, both vegetative check dams and wire net check dams along with vegetation were used for flood hazard minimization. After three growing seasons, the banks of the ephemeral stream were almost fully stabilized. Vegetation based solutions are found to be more effective than the mechanical methods of stream bank stabilization. Bamboo combinations for check dam construction and planting of bamboo behind check dam are both very useful for stream bank stabilization. Vegetation application on flood damaged bare ground was also found to be very successful. Furthermore, some plants species showed almost equal growth performances on both flood-affected and unaffected bare ground. However, more scientific implementation of ecological applications for flood hazard minimization in those affected areas is essential in future.