6 May 2012
Yesterday the Seti River in Kaski District in Nepal was affected by a catastrophic and very sudden flash flood. The flood affected the villages of Kharapani in Sardikhola VDC; Sadal in Machhapuchhre VDC; Yamdi; and Ramghat in Kaski district. To date 15 people are confirmed to have been killed, but the toll will inevitably rise. Initial estimates are that there are a further 36 people missing, including three tourists. The image below shows the aftermath of the flood:
This is an interesting event as the flood was clearly very large. In most cases in Nepal such extreme events occurring without rainfall are associated with either the collapse of a glacial lake dam (a so-called GLOF) or the collapse of a landslide dam. Pradeep Mool of ICIMOD, who has undertaken the definitive studies of GLOFs in the Himalayas, has noted here that the features of this flood suggest that it was not a GLOF, and indicates that a landslide was more likely. Incidentally, most international reports indicate that it may have been triggered by an avalanche, but this would be really quite unusual.
Update: The BBC has a video which appears to show a late stage (i.e. not the main) flood wave at the site, and the aftermath of the flood.
Thanks to Adrian Moon for his hard work on this story; to Tessa/Bobby Rogowski and Cathal Ferris for sending links; and to Ray Duray for highlighting the video.