14 November 2018

Jinsha River landslide: breaching has started

Posted by Dave Petley

Jinsha River landslide: breaching has started

Xinhua, the official news agency of China, is reporting that the Jinsha River landslide at Jomda on the border between Tibet and China has breached.

Chinese authorities on Monday initiated a national emergency response after a landslide hit southwest China, leading to the formation of a barrier lake.  The China National Commission for Disaster Reduction and the Ministry of Emergency Management jointly activated a level-IV emergency response, the lowest level, on Monday, the ministry said in a statement.  A landslide hit the border area between Sichuan Province and Tibet Autonomous Region on Nov. 3, leading to the formation of a barrier lake blocking a section of the Jinsha River.

The article includes a number of images of the site, of which two are worth examining:-

Jinsha River landslide

Aerial image of the Jinsha River landslide at Jomda in Tibet. Image via Xinhua.

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This image appears to be fairly early in the breach process.  Note the evidence of stripping of vegetation on the opposite valley wall – this was a very energetic landslide event.  Meanwhile, this image shows the breaching in more detail:-

Jinsha River landslide

A view from upstream of the Jinsha River landslide at Jomda, Tibet. Image via Xinhua.

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Note the scale of the channel that has been excavated here to initiate the breaching event.  The authorities have succeeded in lowering the height of the dam to an impressive degree, greatly reducing the size of a potential flood.  They have certainly learnt the lessons of the successful management of the Tangjiashan dam ten years ago, and remain the absolute masters of these operation.  Meanwhile, CGTN has tweeted:-

 

But there is very little additional information, and as the area is cloudy there is no satellite imagery.

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