One of my favorite blogs is "Dave's Landslide Blog". For the past four months he has been regularly tracking the buildup of a large lake behind a dam formed by a landslide that blocked the Hunza River in Northern Pakistan. The lake will be overtopping the dam within a few days (possibly as early as tomorrow).
This landslide, called the Attabad landslide, occurred in early January, killed 14 people, inundated several villages and stranded about 25,000 people. More than 50,000 people could be affected by failure of the dam. As of today, it is estimated that there are only 2-3 meters of freeboard before water starts flowing through the spillway that has been engineered through the dam. A glacial lake outburst flood on May 17 raised the water suddenly by 2 meters. All construction on the spillway has ceased due to the imminent breach. Dave's opinion is that the spillway that has been carved is too small to to accomodate the spring runoff flow of the Hunza River. Seepage through the dam has been ongoing, and one possibility is that the dam will fail because of the seepage. Another possibility is that another landslide will initiate overtopping. A third is that water will flow through the spillway with possible erosion.
Most people in this region are farmers whose only assets are their buildings, their land and their crops. They have been tearing apart their buildings to preserve the construction materials, and are in danger of losing their land and crops. It is a terrible tragedy of which most of the world is unaware.
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