Alamgeer Hussain
Focus Humanitarian Assistance Pakistan alamgeer.hussain@focushumanitarian.org
Landslides occur normally in mountainous areas in response to a wide variety of terrain situations
and accelerating processes such as huge precipitation, cloudbursts, earthquakes, floods, and human activity. Continent-wise, Asia suffers the maximum damages/losses due to landslides in general, and the south Asian nations, in particular, are the worst sufferers. Further, among south Asian countries, Pakistan is among the most pretentious countries. In Pakistan, nearly 15 to 20 % of its territory is prone to various degrees of landslide hazard,
frequently affecting human life, livelihood, livestock, infrastructures, and natural resources. Landslides are spread over the north and northwestern part of Pakistan, particularly in KP and Gilgit-Baltistan (GB). The most sensitive areas are Himalaya-Karakoram-Hindu Kush Ranges. Attabad is a remote village in Gilgit-Baltistan situated on the right bank of Hunza River at a ground
distance of almost 125 km from Gilgit city. The village constitutes over 100 settlements with an approximate population of 800 individuals. On the 4th January 2010, a landslide at Attabad was a complex failure on a slope with known stability issues, which involved a massive movement of over 50 Mm3 of rocks and that created a blockade on the Hunza River. Previous fieldwork at the site, by the geologists from FOCUS Humanitarian Assistance, Pakistan, allowed the evacuation of the potentially unstable area. One mudflow that traveled downstream for about 1.5 km, later hit a small settlement close to the river at Sarat, killing 19 people. In the Hunza River, closer to the study area, two historical landslide dams have been recorded, though with limited detail. One landslide dam occurred in 1874 in Salamanabad and another was reported further upstream in between Gulmit and Shishkat in 1958. However, the field evidence for a lake forming behind a landslide dam indicates a much larger feature than any event reported in historical documents. The natural damming of rivers by landslides is a significant hazard in the seismically active
mountainous terrain of the north and north-western parts of Pakistan. There is increased awareness that river-blocking landslides have been more widespread than the documentary records suggest and that Quaternary sediments traditionally
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assumed to be fluvial terraces may need to be re-interpreted. The recognition of palaeo-landslides capable of creating very large lake volumes necessitates a reappraisal of hazard assessment. Therefore, geological and geomorphologic methods to identify landslide hazard potential are especially important in a region experiencing rapid urban development, widespread land-use change, and the construction of water and energy resource projects on major rivers. New GIS and Remote Sensing techniques based on the interpretation of aerial photographs, satellite imagery, digital elevation models, and the development of spatial databases and landslide modeling are enabling more detail about past and present landslide distributions to be generated. The need for vigilance in assessing seismically slope instability hazards is apparent.