Regional to Local Hazard Assessments
Regional to Local Hazard Assessments
 
 
 

Analysis and assessment of hazards at regional and local scales, involves gathering evidence from field investigation and detailed analysis of ground, aerial and satellite remote sensing data.

We reconstruct past events, and model current and future hazard scenarios. Field monitoring of key parameters is central to constructing a reliable picture of the hazard situation.

Output of our analyses leads to various hazard and risk map products and information, which are used for town/rural planning purposes, and the design of mitigation and prevention measures.

 
 

In mountainous terrain, landslides can lead to the damming of mountain rivers, creating a range of high risk scenarios impacting downstream villages and infrastructure. This occurred in the early hours of August 2 2014, when the Jure Landslide in Sindhupalchowk Nepal failed, with an estimated volume of 1’000’000 m3. Approximately 2 km of the major transit route between Nepal and China was buried, along with two villages, taking the lives of 156, injuring 27 and displacing 436 people.

 
 

As a result of the landslide, the Sunkosi river was dammed forming a lake, which extending 3 km upstream. The lake inundated sections of a main highway and a number of houses.

 

 
 

The lake dam, was artificially breached by the Nepalese army, providing a freeboard of 20 metres. Later, the dam breached naturally, reaching a depth of 47 metres.

 

 

 
 

Breaching of the landslide dam, lead to an increase in sediment deposition, thereby damaging and rendering a downstream hydro power facility inoperable. The landslide dam breach resulted in a river base-level elevation increase of 20 metres.