From UPSC perspective, the following things are important :
Prelims level : Himlayan mountain ranges
Mains level : Landslides in India
This newscard talks about the city of Dharamshala where landslides occur frequently.
Practice question for mains:
Q.“Himalayan region is more susceptible to floods and flood induced landslides than the Western Ghats”. Discuss.
Why is Dharamshala more vulnerable to landslides?
- Dharamshala has a slope varying from gentle to steep, depending on different parts of the city.
- It is located in Zone V in the earthquake hazard zoning map of India.
- The large differences in slope between different parts of the city make it more susceptible to critical hazards like landslides.
- The vulnerability of the geologically young steep slopes of Dhauladhar has increased because of anthropogenic activities and illegal construction due to the lack of availability of land.
Why do landslides occur?
- Increasing urbanisation, deforestation and encroachment of areas at high hill slopes, unscientific road cutting and water-intensive agricultural practices contributed to the increase in intensity and frequency of landslides.
- The situation is worse during the monsoon when landslide-prone areas are washed away due to exposure.
- This is due to the demand for living within the city. It is not just the difference between slopes, but also anthropogenic causes that lead to the emergence of hazards like landslides.
Why tourist spots are more vulnerable?
1) Road traffic is high
- During the peak tourist season, the road is marred with traffic jams due to continuous sinking.
- Several factors have continuously contributed to an increase in the road’s vulnerability. The first is Illegal construction and uncontrolled levelling of hillocks along the roads.
- Hillocks are flattened to accommodate housing projects, commercial establishments, etc. The informal sector often starts residing in these areas which are more vulnerable to risks.
- These areas have comparatively lower land values and fewer people come to settle here.
2) Loss in green cover
- The second is a loss in green cover, something that occurs as more people reside within the city, increasing soil erosion, risking the further vulnerability to landslides.
- Due to the loss of green cover and steep gradient of the slope, water is not absorbed in the soil and washed away very quickly.
3) Damaged topography
- The third is the unscientific manner of cutting hills for widening roads and construction.
- This causes the sinking of roads, which affects road width and causes traffic interruptions.
4) Sewage failures
- The fourth is the absence of a sewerage system in the area. Due to unavailability of sewerage systems, people construct septic tanks that are unsafe for soil strata.
- Water from septic tanks drains to the upper layer of soil that has loose soil, making areas more vulnerable to damage from landslides.