Nepal is a small developing country located smack bang in the middle of the Himalayas – the highest, and in my definitely not biased opinion, most beautiful, mountain range in the world. The trekking opportunities provided by the Himalayas are a major driver of Nepal’s vital tourism industry. However, the geological and geomorphological complexity of the Himalayas also presents major challenges to Nepal’s social and economic development. Not least is the problem of landslides, which are estimated to cause a staggering average of 78 fatalities every single year! Considering how much is known about landslide hazard and management, this to me is a completely unacceptable figure.
Village near Kodari, Nepal, destroyed by a rockfall triggered by the 2015 Gorkha earthquake.
The question is, how do we reduce the impact of landslides in one of the poorest and most mountainous countries in the World?
Does Nepal simply have to accept landslides as the price to pay for being located where it is? Or can more be done to better understand and mitigate landslide hazard in this highly susceptible region? It is this question which ultimately motivates my PhD research into how earthquakes may have long-term influences on landscape susceptibility to landslides in Nepal, and how this information could be used to improve our ability to predict future landslides.
I am currently just over 15 months into my PhD, and have been lucky enough to conduct fieldwork in Nepal on two separate occasions. As well as collecting data, these trips have given me the opportunity to visit and speak to a range of local people and government agencies. These conversations have been eye-opening, and have highlighted to me some of the big issues that Nepal is facing as it tries to better manage the problem of landslides. For example, on my most recent trip I visited Langtang, a rural valley located high in the Greater Himalayas. This valley was devastated by landslides triggered by the 2015 Gorkha earthquake, including the ‘Langtang Avalanche’ which completely buried an entire village, killing an estimated 300 people. I spoke to one local who told me that a similar devastating landslide wiped out another village approximately 80 years ago, but that it was simply rebuilt further up the valley – this new village was the one destroyed in 2015. I asked him what he thought the solution to the landslide problem was. He laughed and said “for everyone to leave the valley and go to Kathmandu”.
The back-scar and deposits of the devastating Langtang Avalanche. The deposits seen in the bottom of the photo have buried an entire village, including over 300 people. Excavation has sadly been impossible due to the sheer volume of material.
I encountered this viewpoint that nothing could be done about landslides on multiple occasions. But is it true? Was everything that could be done in Langtang already being done? I’d argue not.
Langtang had no hard or soft engineering, no warning provisions (bar two rusty ‘beware of rockfalls’ signs), and no land use or building planning – as evidenced by the fact that a new village was currently being built less than 100 m from the debris deposits of the Langtang Avalanche! Furthermore, a basic susceptibility map derived from my field data showed that part of the upper portion of Langtang Valley was significantly safer than the lower and middle portions – something we’d surmised in the field by just visually assessing the geomorphology.
One of the only hazard management attempts we came across in Langtang Valley. (photo credit: Tim Webster)
So why didn’t locals have this information? Why were they continuing to rebuild in the more dangerous lower portions of the valley? It’s understandable that there was no hard engineering, it’s expensive, but planning rules and information on susceptibility are things that should be held by the Nepal Government Geological Department. So why wasn’t this information being communicated to local communities?
This question can be answered by visiting the Nepal Geological Department. The answer, they didn’t actually have this information either! Despite the fact that multiple papers on Nepal landslide susceptibility exist, the information just doesn’t seem to have gotten to the one place it needed to be. This highlighted to me that a major problem in Nepal isn’t the geology, or a lack of understanding of the science, it’s a lack of communication between the international research community and the local stakeholders who actually need this information.
I don’t think landslides in Nepal will ever be totally avoided, the geology and geomorphology is simply too extreme. But I can’t help but wonder how many lives could potentially be saved if basic, existing, information on landslide susceptibility was effectively communicated to local communities. As I go forward with my PhD, these experiences have motivated me not just to pursue the ‘science’, but also to ensure that the research I produce gets to where it needs to be. I think this is something that all of us environmental scientists need to think about as we continue our projects.
From right to left, Tim Webster (my field assistant), Ngima (Our wonderful guide) and me, at about 4500 m in Langtang Valley, during my second field trip in October 2018.