21 September 2010
Tangjiashan again – and a possible new Chinese flowslide
Posted by Dave Petley
Back in 2008 I dedicated a great deal of space on this blog to the extraordinary efforts by the Chinese Army to draining the landslide lake at Tangjiashan, just above the town of Beichuan, which was created by the May 2008 Wenchuan Earthquake.
These efforts were ultimately successful, but in my visit to the site in Spring 2009 it was clear that a threat remained at the site in the form of another block of material that was showing signs of deformation. Over the last few days this area has received very high levels of rainfall. Yesterday, Xinhua reported that a 300,000 cubic metre block has detached from the scarp above the barrier, and blocked the river to a depth of 10 metres:
China is well-versed in dealing with these hazards, but given the magnitude of the destruction in the Beichuan area, such events must cause great heart-ache.
It is clear that the elevated level of landslide activity in the aftermath of the landslide is a major issue. I am travelling to Chengdu on Sunday, so will see whether I can ascertain more information about these issues.
Meanwhile, Bloomberg reports a probable flowslide failure in a tin mine in Guangdong yesterday:
China has been impacted by a series of these events in recent years, including one that caused multiple fatalities in 2008. There appears to be a strong need to improve the safety of these facilities before another major accident occurs.