Building resilience against landslides

Source– The post is based on the article “Building resilience against landslides” published in “The Indian Express” on 23rd August 2023.

Syllabus: GS1- Geography. GS3- Disasters

Relevance: Space exploration

News– The deaths and destruction by landslides in Himachal Pradesh last week have led to much-needed attention on the Himalayan ecosystem.

What are the reasons behind the vulnerability of Himalayan ecosystem?

Tectonic or neo-tectonic actions and surface processes including erosion, weathering, and rainfall impact the Himalayan ecosystem.

Environmental vulnerabilities are exacerbated by extreme climatic events driven by climate changes. It results in occurrences like avalanches, landslides, debris flow, glacial lakes outburst floods, landslide lakes outburst floods, and rapid floods.

Climate change has detrimental effects on glaciers, river systems, geomorphology, and biodiversity.

These events contribute to the instability of the mountain system. Moreover, the Himalayan region faces additional pressure due to human activities.

Mountainous areas are typically characterized by slope instability and a susceptibility to landslides.

Various factors influence these occurrences. These include slope steepness, elevation of hills, rock durability, forest coverage, urban development, and the presence of loosely consolidated sediment.

Activities such as river flow, alteration of the base of slopes, and deforestation contribute to the vulnerability of a region to landslides. Factors like debris flow and underground water weaken slopes, making them prone to sliding.

The collision between the Indian plate and the Eurasian plate in the Himalayan region generates subterranean stresses that are discharged as earthquakes. It causes fractures and weakens the litho-structures near the surface of the mountains.

Way forward-

There is a need to create vulnerability maps of Himalayas and classify regions into risk zones ranging from the most vulnerable to the least.

Monitoring can be facilitated through web-based sensors like rain gauges, piezometers, inclinometers, extensometers, InSAR, and total stations.

To comprehensively assess the situation in the Himalayas, the establishment of a Himalayan States Council is imperative.

This council should aim to replicate scenarios of hazards resulting from natural occurrences, environmental deterioration, climate-related events, and human interventions in hill towns and areas.

The disaster management agencies of the respective states should collaborate within this centralized council.

The Himalayan region possesses valuable assets such as glaciers, river systems, mineral deposits, geothermal and hydrocarbon energy reserves. These could be harnessed. Nonetheless, a delicate equilibrium must be maintained between exploiting these resources and ensuring ecological sustainability.

Urban planning must accommodate the unique characteristics of mountainous terrain. Limitations should be placed on extensive constructions. Proper drainage systems need to be established.

Slope cutting should be carried out scientifically, and an emphasis should be placed on constructing retaining walls and adhering to building regulations.

It is crucial to conduct high-resolution mapping for all towns and evaluate their load-bearing capacities as fundamental steps in the formulation of building codes.