13 August 2021
Nalda: a valley-blocking landslide in Himachal Pradesh, India
This morning (Friday 13 August 2021) a major landslide occurred near to the village of Nalda, in Lahaul and Spiti district in Himachal Pradesh, northern India, blocking the Chenab River. The landslide event itself was captured in a video that has been posted to Youtube:
The landslide has left a large barrier across the Chenab River close to Nalda. The image below, from Tribune India, provides an overview of the situation:
This is not likely to remain breached for long given the topography of the land and the form of the barrier – indeed some reports suggest that some flow has been re-established. But even a few hours of impounded water has the potential to generate a substantial local flood, so there is a substantial hazard for villages downstream.
Note the very clear planar structures in the landslide scar. The failure is clearly defined by two existing joints or faults, meeting with a c.90 degree angle. Note also the landslide scar immediately to the left of the landslide scar. That must also have been a substantial failure event.
This landslide comes on the back of a significant landslide in India on Wednesday, when a slope above a road in India collapsed, burying several vehicles including a bus. Recovery operations continue at the site, but at the time of writing 15 bodies have been recovered. There are fears that there may be substantially higher levels of loss. The Indian Express reports that Chief Minister Jai Ram Thakur has indicated that up to 60 people were feared trapped under the debris at the time of the accident. Rescue operations are being hampered by ongoing instability on the slope.