Landslide Disaster

There is a big news from Colombia in South America regarding the deadly landslide causing widespread destruction and damage. Landslide is one of the natural or man- made hazards and can be disaster if it affects the human population directly or indirectly. It is to be noted that it happens only in those places which have mountains so it is not found in plain areas. Each year many people around the world are affected by landslide and it is common in many countries including Nepal during the rainy seasons. Landslide in Krishnabhir on Mugling highway is well known in Nepal for its yearly blockage during Monsoon time causing the disruption in transport disruption and break in supply chain to Kathmandu city.

In 1949 landslide in then USSR killed 12,000 people, Honduras landslide ( 20 Sep 1973) killed more than 2,000 people and in the latest event landslide in China (7 Aug 2010) killed 1,756  people. Many factors are involved in landslide like nearby the fault area, slope of the mountain, proximity to river and so on.Sometimes earthquake also induces instability to the weak mountain and causes the landslide.Figures below from USGS shows the before and after the landslide event where we can see closely the damage to the roads (red circle). 

Landslide images  (Up: Before and Down: After)

There are many ways to tackle the landslide and one is the landslide mapping and do land-use according to the hazard. Beside that, retaining wall and other engineering methods can also be employed.Forestation of affected area can also help a lot in controlling the rain water and thereby reducing the chance of landslide in very steep slope areas as in Nepal.Water Induced Disaster Prevention (DWIDP) was established on 7 February 2000 under the Ministry of Water Resources  to tackle with the water induced disaster including landslide in Nepal. Next blog will talk about the disaster scenario of Nepal including landslide.