Incidents of landslide on upward trend, effective measures required: Experts

y Narayan Dhungana, Kathmandu, July 13: A total of 4,610 incidents of flood and landslide took place across the country in the past 12 years (from 2068 BS to 2079 BS). Of them, 1,816 incidents are flood-related, and 2,794 are landslide-related.

According to the National Disaster Risk Reduction and Management Authority (NDRRMA), a total of 2,360 people lost their lives to the disasters (876 died from floods and 1,484 from landslips). Other 563 people had gone missing in flood-related incidents. A total of 15,769 houses were destroyed completely (11,878 by floods, and 3,891 by landslides) damaging properties worth over Rs 35.2 billion.

Lately, the incidents of landslides and human losses caused by them have gone higher as compared to that of flood. In the past three months (from 14 April to 10 July, 2023), nine people were killed due to 89 incidents of flood while 19 people lost their lives to 248 incidents of landslide.

When data from the recent past five years is analysed, the incidents of landslips and human losses have increased as opposed to that caused by floods, said the NDRRMA.

A total of 1,929 landslides took place in the immediate past five years (334 in 2075, 434 in 2076, 489 in 2077, 344 in 2078 and 328 in 2079 BS), and 579 people were killed in landslip-related incidents in the past three years (301 in 2077, 182 in 2078 and 96 in 2079 BS).

In the past five years, a total of 214 people were killed in flood incidents (17 in 2075, 73 in 2076, 42 in 2077, 63 in 2078 and 19 in 2079 BS).

Digging roads rampantly is a major factor behind increasing landslide incidents, said disaster management expert Dr Krishna Chandra Devkota, Vice Chairperson of the Provincial Policy and Planning Commission, Gandaki Province. This would continue in the days to come if digging roads without carrying out a proper study continues, he warned. “Factors like dug road walls being left bare without proper management, road infrastructures constructed without carrying out a geological and environmental impact assessment (EIA), and failure to focus on making arrangements after identifying risky areas are blamed for landslips,” he said.

Managing landslips requires substantial suggestions from technical and the construction of infrastructures as per guidelines set by the Sustainable Development Goals, he suggested. Today’s nature of flooding was different than in the past, and flood-related incidents have been also decreasing, said the NDRRMA executive chief Anil Pokharel.

Lately, incidents of flood have been shifting from the Tarai towards hilly and mountainous regions. Devastating flooding occurred in Melamchi two years ago, and floods are taking place in Manang and Mustang. Factors like embankment constructions, the construction of disaster-resilient houses and structures, and a pre-warning system for floods have helped a lot to save the Tarai from floods to some extent, he said.

“We have invested in the Department of Hydrology and Meteorology for six years. We have almost been on par with India in terms of the pre-warning system. As a result of the whole thing, incidents of flood have been decreasing,” he claimed, adding, “Increasing incidents of landslide have taken place due to increasing human settlements. There have been unmanaged settlements. Private houses have been constructed without taking into account disaster risks. Core parts of the soil are absorbing a large amount of rainwater, thus weakening underground rocks resulting in landslides.” Besides, some unmanaged development activities have contributed, he said.

Pre-warning system, management and identification of risk are required     

Lack of substantial identification of risky areas has been a major concern when it comes to containing landslides, according to experts. Although rain estimation is effective, estimation of its results and landslide risks are yet to be effective, they said, adding that in some cases, lack of estimations in some risky areas and risk management have hit the matter.

Some local levels lacking related technology, skills, resources and research and uniformity in research and results have added to the problem, they said.

Incidents of the landslide have occurred in Nepal due to a lack of real-time data about the disaster and substantial research and studies, said geologist Dr Ananta Man Singh Pradhan, senior divisional engineer for the Water Resources Research and Development Centre.

“The exact identification and estimation of risky areas are required,” he said. In the context of the soil getting hotter every year, precautions should be adopted, and alternatives sought to dig the roads, said Dr Sanjaya Devkota, executive director of the Forum for Energy and Environment Development. Proper EIA is required to construct roads, he added.

“Identification of the causes of landslides and their seriousness, and risks should be assessed. After analysing all these things, preventive measures should be sought,” suggested Dr Ranjan Kumar Dahal, associate professor for the Central Department of Geology, the Tribhuvan University. The NDRRMA admitted to a lack of substantial work and programmes taking place to reduce landslides.

There is a need to identify problems in the scaling, resolution and aim in the course of estimating landslide risky areas, and for this, experts’ assistance are required, said the NDRRMA’s undersecretary Rajendra Sharma.