Environment

Why Landslides Have Been Leading to a Higher Loss of Life in Recent Times

Relentless deforestation, indiscriminate mining and construction activities have contributed to the rising death toll.

View of a neighbourhood destroyed after landslide in Manizales, Colombia. Credit: Reuters/Santiago Osorio

View of a neighbourhood destroyed after landslide in Manizales, Colombia. Credit: Reuters/Santiago Osorio

The tragic loss of over 100 lives due to a massive landslide in China on June 23 has come soon after an even higher loss of lives in Bangladesh. On June 12, following heavy rains, there were a series of landslides in the three hill districts of Rangamati, Chittagong and Bandarban, which killed over 156 people.

The tragedy continued in the next few days as there were some more landslides. Raaz Ahmed, the head of Bangladesh’s disaster management department, called this the worst landslide disaster in the country.

Just a little earlier, in the last week of May, landslides and mudslides with floods claimed over 100 lives in Sri Lanka. During the last month, several destructive landslides have been reported from India as well.

Experts say that at the world level the mortality from landslides has been much higher than what was estimated earlier. According to the much discussed Durham Fatal Landslide Database, the actual number of landslide-related fatalities during 2004-10 was actually roughly five to ten times the estimates mentioned earlier. The previous estimates for this period ranged between 3,000 and 7,000 while the new estimate given by this database is 32,300.

Dave Petley, who led the efforts to prepare the Durham Fatal Landslide Database at the International Landslide Centre in Durham University, included several research papers and reports from aid agencies along with government data to prepare his database. Clearly, estimates based on government data alone underestimated the fatalities to a considerable extent.

According to Petley, “We need to recognise the extent of the problem and take steps to manage what is a major environment risk to people around the world. Our database will enable us to do so by identifying areas most at risk.”

Risk factors

A question that is being increasingly asked is why landslides are proving so costly in terms of loss of human lives in recent years. At the time of the latest landslides in Bangladesh, two factors were commonly mentioned. One was the relentless deforestation – leading to denudation of the hills, thus making them more vulnerable to landslides. The second was the increasing poverty of a large number of people which had forced them to settle in more dangerous areas where others do not want to live. Hence, the poor are forced to settle in highly hazardous zones and over a period of time this dangerous area can turn into a dense habitation.

Another main factor is that without giving due consideration to geologically weak formations and the special vulnerability of certain areas, indiscriminate construction and mining activities are taken up, which also involve blasting work. In the process, previous slide zones become more active and several new slide zones are created.

A few years ago, I visited the villages of Doon Valley which had been devastated by mining. Here, villagers told me that when stones and boulders fell on their villages from landslides, they felt as if their village was being bombarded by some invading force. This was directly related to the impact of indiscriminate mining.

Then, at the time of the indiscriminate construction activities for the Tehri dam project, several villages were devastated by landslides, and later, villagers living above the waters of the newly created lake were found to be living in constant fear of their houses sliding towards the water.

More recently, the indiscriminate expansion work on the Kalka-Shimla highway has endangered villages like Sanwara and Makoti as cracks have appeared in their fields due to landslides. Meanwhile, there are billboards warning drivers about the sudden falling of huge boulders and rubble.

Many such examples can be given to show that caution is not exercised by miners and builders even in highly vulnerable areas, which leads to both a higher incidence and intensity of landslides. Of course, the technology of protective works has progressed but this by itself cannot help if caution is thrown to the wind such that more difficult landslide zones are being created where these could have been avoided.

Clearly, safety has to be prioritised, particularly in the more vulnerable areas so that the increase in landslides can be avoided. As far as the areas which have already become highly insecure are concerned, apart from taking up protective works and plantation, the possibility of satisfactory relocation to safer areas should also be given timely attention wherever necessary.

Landslide zones should be properly mapped and safety works taken up with active participation of local communities, including women and weaker sections of the society.

Bharat Dogra is a freelance journalist who has been involved with various social movements and initiatives.