8 July 2022
Shifting the blame for the deadly landslide at Tupul in India
Posted by Dave Petley
Shifting the blame for the deadly landslide at Tupul in India
Recovery operations continue at the site of the 30 June 2022 landslide at Tupul in Northern India. The latest news is that 49 bodies have been recovered, whilst a further 12 people remain missing. The likelihood of recovering their remains is probably diminishing with time. In total, 29 of the victims were soldiers billeted on the landslide site, who were reportedly providing security to the project.
Inevitably, attempts are now being made to shift the blame for the disaster. The New Indian Express provides two perspectives. First, they report the words of an anonymous senior geologist from the Oil and Natural Gas Corporation:-
“We have loose soil here. The rocks are hard only in the deeper portions. So when it rains incessantly or heavily, chances are that the soil will erode,” the geologist, who has worked in the region, said requesting anonymity…”To avoid such incidents where development projects are coming up, we must ensure maximum plantations. Only the plants with roots that can reach the sub-surface should be planted in consultations with experts,” he said, adding that in Uttarakhand, which has hard rocks, the retaining walls should have steel nets to keep the earth stable.
Vegetation is of course important in landslide management, and it brings many other benefits. But there is no evidence that vegetation, or lack thereof, was the cause of the landslide at Tupul. Indeed, the deep-seated nature of the failure indicates that vegetation was probably essentially irrelevant. The clear evidence of slope cutting is likely to have been far more significant, although as I noted previously this needs to be investigated properly.
Secondly, the article quotes one or more railway officials in relation to the landslide:-
“When a hill is cut for a project, the angle and the slope need to be maintained. It was adhered to,” he said … A railway official blamed jhum cultivation for the recent incident.
“Rainwater had got accumulated at the site, rendering the soil soft. That place is not a natural basin,” he said.
Jhum cultivation is a shifting form of agriculture in which the forest is cut down and burnt, and the land is then farmed for a small number of years before being abandoned. In the traditional form the land is allowed to recover, but a shift to more intensive land use means that the time period between cycles has often been reduced. The consequences can be extremely environmentally destructive.
There is little doubt that jhum cultivation can be have adverse outcomes for the land, and there may be some evidence that it has been practised in the Tupul area. However, I will leave it to readers to consider whether this is the probable cause of a deep-seated landslide at this site:-
A Google Earth image of the site of the 30 June 2022 landslide at Tupul in northern India.
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If losses from these types of landslides are to be reduced then there is a need for an honest conversation about the likely causes.
Dave Petley is the Vice-Chancellor of the University of Hull in the United Kingdom. His blog provides commentary and analysis of landslide events occurring worldwide, including the landslides themselves, latest research, and conferences and meetings.
Spot on about deep-seated slides: The vegetation is just along for the ride. However, dense, mature vegetation can often mitigate shallow failures during short down-bursts through root strength and raindrop interception slowing down the delivery rate to the ground.
The plants were along for the ride much like the glaciers were along for the ride on the landslide at Mount St Helens in 1980. The water input and water pathways though affect the lubrication and liquefaction of slopes, and in the case of MSH the rapid depressurization of superheated water infiltrating the slow slumping of the slope. The water input is critical to the eventual calamity and is modified by the vegetation and farming practices and water routing. The landslides on that slope have been big and frequent as shown on the google image. One previous huge slump into the river led to a big meander, which then resulted in the river undercutting the slope that failed. More river flow, more undercutting more water input to the unforested and recently cleared slopes all likely contributed. Lots of work for engineers to do here, to just try to prevent ongoing failures. Much could have perhaps been prevented as well. Climate change, land clearing, farming practices, and most of all engineering work done to build the rail all likely contributed. It likely will be a dangerous location for a long time and needs lots of engineering work and improved land surface practices. The engineer has a point for sure that farming practices and climate change played a role, but the building of the rail across a slope so clearly being undercut by the river meander, forced by an earlier big slide is the cause. I hope no one else gets killed or harmed. It will be a difficult situation to resolve, but it likely can be done with lots on ongoing (and costly) maintenance. Laying blame on farming practices is not the solution here. Better engineering and building design and practices are the solutions. Climate warming impacts with more rain and heavier rain, and intermittent deluges likely will be the norm, and engineering needs to include all human and naturally enhanced impacts before they happen and better prevent the disasters. That is possible but it must be done way before this rail was planned across this slope and built.
Hmmm. To me, it’s readily apparent that the entire mountain front (at the large scale) shown in the image is a fault-faceted slide-front, and the toe of the slide is the immense pile of rubble across which the roads and other human features are seen and around which the river flows. Construct anything in such a setting, and expect the obvious–landslides. I suspect that “roots” like the roads are along for the ride.