Hazard risk scenarios
Hazard risk scenarios
 
 
 

Hazard and risk scenarios are an integral component of our HRVAs, and provide crucial information about the type of events that may endanger or impact human settlements and livelihood. Through scenario modelling, our goal is to understand and quantify the magnitude and intensity of the most plausible disaster events.

We use scenarios to produce hazard and risk maps, perform detailed risk analyses, and design mitigation and prevention measures. Scenarios are calculated using both empirical and numerical methods.

 
 

Oblique view of the village Abe Barek located in Afghanistan which was hit by a landslide in 2014. The landslide destroyed over 80 buildings and caused over 300 fatalities which still remains unconfirmed. Detailed analysis of satellite images acquired prior to the event and satellite radar interferometry from preceding years, showed that the landslide was active prior to failure in 2014.

 
 

Runout simulation of the failure event which occurred in 2014 using the model RAMMS. The map indicates the extend and flow height of the landslide runout with largest deposition depths on the valley floor. The landslide deposits dammed the river valley and created a lake.

 
 

Runout simulation of a conservative, future landslide event using the model RAMMS. The map indicates the extend and flow height of the landslide runout. Although the scenario is more restricted in its extent as the 2014 event, a considerable area within the vicinity of Ab Barek has an elevated hazard potential.

 

 

 
 

Preliminary risk zonation map based on hazard scenario modelling for the 2014 landslide catastrophe. The buildings coloured red and orange, which are visible in the satellite imagery, acquired prior to the landslide event of 2014, were at high and medium risk respectively.

 
 

Preliminary risk zonation map based on a future landslide hazard scenario. The zonation map shows a change in the risk potential for buildings, between the 2014 and a future landslide event. Detailed mapping using satellite imagery and DEM analysis indicates that a potential landslide mass is evolving.

The background satellite image, acquired shortly after the landslide event of 2014 shows the actual runout of the landslide, where it destroyed a number of buildings. The black area to the left of the image is the lake formed as a result of the landslide dam.