Man-made disaster, was a loose way of describing landslides caused by reckless construction, be it in Uttarakhand or Himachal Pradesh. Now a research by the University of Sheffield has for the first time revealed that it was no casual statement.
While the trend is global, Asia is the most affected continent. The number one country is India, which accounts for 20 per cent of these events. It is also the country where human-triggered fatal landslides are increasing at the highest rate, followed by Pakistan, Myanmar and the Philippines, said Dr Melanie Froude, the lead author of the study. According to her: “All countries in the top 10 for fatal landslides triggered by human activity are located in Asia.”
Construction works, legal and illegal mining, as well as the unregulated cutting of hills to carve out land on a slope have indeed caused most of the landslides between 2004 and 2016, says the study. Covering more than 4800 fatal landslides in the period, the new research points out that more than 50,000 people have been killed in the course of these calamities. Worse, the research points to the fact that landslides resulting from human activity have increased.
The study calls for global action on preventable slope accidents.
The team found that more than 700 fatal landslides that occurred between 2004 and 2016, had a human fingerprint.
Froude, a postdoctoral researcher in the University of Sheffield’s department of geography said, “We were aware that humans are placing increasing pressure on their local environment, but it was surprising to find clear trends within the database that fatal landslides triggered by construction, illegal hill cutting and illegal mining were increasing globally during the period of 2004 to 2016.”
In the Himalayan mountain region, especially in Nepal and India, many of the fatal landslides triggered by construction occurred on road construction sites in rural areas, while in China many happened in urban building sites.
Froude said: “The prevalence of landslides in these settings suggests that regulations to protect workers and the public are insufficient or are not being sufficiently enforced. In the case of roads, maintaining safety during construction is difficult when it is economically unviable to completely shut roads because alternative routes involve substantial 100 mile-plus detours.”
But they are entirely preventable, she says. What is required include appropriate regulation to guide engineering design, education and enforcement of regulation by specialist inspectors.
Professor Dave Petley, vice-president for research and innovation at the University of Sheffield started collecting data on fatal landslides after realising that many databases on natural disasters were “significantly underestimating the extent of landslide impact.”
While earthquakes and storms are deadlier, landslides cause a significant number of fatalities. The most tragic event identified by the researchers was the Kedarnath landslide in June 2013, which resulted in over 5,000 deaths. It was, however, due to extreme weather conditions that caused flash floods and massive mudflows, which affected thousands of religious pilgrims trapped in a mountain area.
Professor Petley collected data on fatal landslides from online English-language media reports, from 2004. To confirm the news stories were accurate, Professor Petley, and more recently Froude, who reviewed all landslide accounts checked each report whenever possible against government and aid agency articles, academic studies or through personal communication. Details about the landslides, such as location, impacts or cause, were added to their Global Fatal Landslide Database.
While 75 per cent of landslides in the database occurred in Asia, the areas most affected are in Central and South America, the Caribbean islands, and in East Africa. In Europe, the Alps is the region with the most fatal landslides.
The researchers also found that 79 per cent of landslides in their database were triggered by rainfall. Most events happen during the northern hemisphere summer, when cyclones, hurricanes and typhoons are more frequent and the monsoon season brings heavy rains to parts of Asia.
The Natural Hazards and Earth System Sciences study highlights that fatal landslides are more common in settlements, along roads, and at sites rich in precious resources. They occur more frequently in poor countries and affect poor people disproportionately, the researchers say.
Froude pointed out that landslides triggered by hill cutting were a problem in rural areas, where many people illegally collect materials from hillslopes to build their houses.
“We found several incidences of children being caught-up in slides triggered as they collect coloured clay from hillslopes, for decoration of houses during religious festivals in Nepal. Educating communities who undertake this practice on how to do it safely, will save lives.”