Partial breaching of Hattian Bala Landslide Dam formed in the 8th October 2005 Kashmir Earthquake, Pakistan

The 8th October 2005 Kashmir Earthquake of magnitude 7.6 triggered a huge landslide 3.5km upstream of Hattian Bala town in the state of Azad Jammu Kashmir of Pakistan. The debris mass blocked two tributaries of the Karli branch of the Jhelum River and was breached on 9th February 2010. This debris dam provided us with a rare opportunity to keep careful and continuous eyes on its post-earthquake behavior especially as it was a serious threat to people living along the lower reaches of both the Karli and Jhelum Rivers. This paper describes post-formation behaviors of the debris mass, breaching-inflicted changes of not only the debris mass but also both upstream and downstream reaches based upon laser-scanned images of landforms and Differential Global Positioning System survey results.