This blog provides commentary on interesting geological events occurring around the world in the context of my own work. This work is, broadly, geological fluid dynamics. The events that I highlight here are those that resonate with my professional life and ideas, and my goal is to interpret them in the context of ideas I've developed in my research. The blog does not represent any particular research agenda. It is written on a personal basis and does not seek to represent the University of Illinois, where I am a professor of geology and physics. Enjoy Geology in Motion! I would be glad to be alerted to geologic events of interest to post here! I hope that this blog can provide current event materials that will make geology come alive.

Banner image is by Ludie Cochrane..

Susan Kieffer can be contacted at s1kieffer at gmail.com

Thursday, May 20, 2010

Landslide Dam is about to be overtopped

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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