Assessing and Modeling Landslide Lake Outburst Floods Along the Araniko Highway in Nepal
Patrick M. Holmes
Landslides are commonly portrayed as unstable slopes collapsing and causing a blockage on a roadway. Though this does occur in mountainous terrain often, landslides can have a greater impact when collapsing in a river basin. River basins around the world are surrounded by unstable slopes, which can fail due to precipitation and erosional processes. When these slopes fail, the landslide generally causes blockage in the river system bringing the flow to a halt and forms a pond behind the blockade. The problem created from this landslide blockage is what is known as landslide lake outburst floods (LLOF). When the water builds up enough to breach the sediment loose, a flood burst out interacting with the mountainous landscape, impacting people and infrastructures downstream. Buildings, houses, and properties have been damaged from these outburst floods not only from the high discharge of the water but plucking of large size sediments. This study will aim to identify unstable slopes in the Himalayan Mountains where monsoonal rains and frequent seismic activities lead to landslide occurrences, specifically along the Araniko Highway. The Araniko Highway is a heavily travelled highway that connects Kathmandu to China and is considered one of the most dangerous highways in the world. This research’s main goal is to identify specific slopes along the Araniko Highway that are susceptible to slope failure and end up creating a river blockade. Eventually, that blockade could lead to a LLOF, and the water that has built up behind the sediment dam can negatively impact man-made infrastructures from the failure of the dam. Resource platforms such as Google Earth, ArcGIS, and HEC-RAS 1D will be utilized. HEC-RAS will be used to create a model/cross-section of the LLOF after failure in order to predict how a landslide can impact the flood discharge and occurrence. ArcGIS and Google Earth will be used to identify the susceptible areas that could create the landslide dam. The modelling results will help create remediation ideas or evacuation plans for people in the area who are at severe risk of danger.
Zelalem K. Bedaso, Chia-Yu Wu
Primary Advisor's Department
Stander Symposium Posters, College of Arts and Sciences
"Assessing and Modeling Landslide Lake Outburst Floods Along the Araniko Highway in Nepal" (2021). Stander Symposium Projects. 2188.