28 July 2012

A landslide is rapidly destroying a World Heritage site in India

Posted by Dave Petley

The ever impressive Save the Hills blog in India has a post including a set of images of a retrogressive slope failure in India that is threatening the railway shed at Tindharia.  This is a railway settlement built by the side of the famous Toy Train – the Darjeeling Himalayan Railway (DHR).  The DHR was constructed by the British back in 1881, and was designated a World Heritage Site in 1999/2000.  The construction of this mountain railway is an astonishing achievement, and in this terrain maintain it is a very substantial challenge.  Unfortunately, in 2010 the track was severed by a landslide at Pagla Jhora (picture by David Mead):

The line is still blocked at this point.  Then in 2011 another landslide severed the line at Tindharia (picture from Hari Pasod Sharma):

The result is that there is now no service on the upper parts of the line, with only a very limited service in the lower portions. This Google Earth perspective image from 2008 shows the Tindharia site quite well – the large building is the railway maintenance shed, with the line looping around it.  The landslide has occurred in the heavily eroded terrain below the line:

Unfortunately, on 19th-20th July 2012, the Tindharia landslide reactivated considerably during a heavy monsoon rainstorm, and has now removed both a substantial section of track and started to damage the walls of the shed.  Save the Hills has an image of the site at the crown of the landslide:

DHR has an overview of the landslide, showing the degree to which it has retrogressed in the recent event (the labels are theirs not mine):

This is clearly now a crisis for the railway.  Even without further retrogression (which does seem likely), the damage is now quite profound.  Reopening the line will be exceptionally difficult without very large-scale engineering works.  Further retrogression of the landslide will lead to the loss of these historic buildings.  In turn, the landslide will be causing widespread economic costs through the region through the loss of both communication links and tourism.

This does seem to be an issue that deserves more attention.  Your thoughts on possible solutions or ideas for mitigation are welcome.