6 March 2017
Righa in Nepal: another landslide associated with a hydropower project
Over the weekend, various media outlets in Nepal reported a landslide near to Righa in Baglung district in Central Nepal, which briefly blocked the Daram River (although the blockage has now cleared). This landslide appears to have claimed the life of a local woman. Online Khabar reported the landslide as follows:
A landslide that occurred during the construction of a road for a hydropower project in Manewas of Righa-7, Baglung district, has partially blocked the Daram River. This has also shut the Mid-Hill Highway.
Two things to note here of course. First, that once again we see a significant landslide associated with a hydropower project (a point that I make frequently) and secondly, that this landslide was triggered by excavation. Interestingly, MyRepublica suggests that the problem may have been pipeline construction alongside the road for the HEP plant:-
According to Badri Sharma, chief division engineer at the mid-hill highway in Baglung, the ‘dry landslide’ was a result of the digging of land along the highway for laying pipes to produce energy by the Daramkhola Hydroelectricity Project Limited.
“When they asked for permission, we had told them to lay pipes toward the cliff as the edge of the highway was quite steep, ” said Sharma. He informed that clearing the rocks and land will take some time. “I have already asked the construction companies and Hydropower project working in along the highway to fix the problem and they assured to make the highway ready in about five-six days,” said Sharma.
Judging by images the landslide itself is quite significant in size (via the Gorkha Post):
There is also a collection of images of the landslide in a Youtube video that is available online:
Perhaps the most revealing element is this image of the headscarp area of the landslide at Righa:-
In common with the images of the landslide deposit, this suggests that the slide is in deeply weathered, dry soil. Such a landslide should in general be avoidable with good engineering practice, if excavation does indeed to be the cause of this landslide. There does appear to be some evidence that the landslide might be associated with a highway and associated works – this image from MyRepublica shows the crown of the landslide: