Date: 24/08/2022

Relevance: GS-3: Conservation, environmental pollution and degradation, environmental impact assessment Disaster and disaster management.

Key Phrases: Eco-sensitive Himalayan Zones, Rise in the Frequency of High-Energy Cyclones and Droughts, Glacial Lake Outburst Floods, Landslide Hazard Zone Maps, High-energy Cyclones and Droughts, Glacial Retreat due to Climate Change

Context

• The torrential rains have triggered flash floods and landslips in Himachal Pradesh and Uttarakhand taking a toll of at least 25 lives.
• Monsoon rainfall over India is 8% more than what is usual for this time of the year.
• While this might prove beneficial for agriculture in some regions, it also means floods and concentrated downpours with devastating consequences.

Key Highlights

• Around 75% of India’s annual rainfall is concentrated in just four months and thus, unevenly waters the country’s highly diverse terrain.
• It is, therefore, inevitable that some spots are far more vulnerable and bear a disproportionate impact of climate disasters.
• Cloudbursts and flash floods in recent years have become a regular feature in the hill state of Himachal Pradesh.
• However, the loss of life caused by natural calamities can be mainly attributed to increasing human interference, particularly in eco-sensitive Himalayan zones.
• A recent report released by Himachal Pradesh’s Department of Environment, Science, and Technology underlines that mountain areas are highly vulnerable to natural disasters, where development over the years has compounded the problem by upsetting the ecological balance of various physical processes.
• Monsoon rain patterns are being disrupted leading to a rise in cloudburst-like events as well as a rise in the frequency of high-energy cyclones and droughts.

Devastating impacts of the landslides and flash floods:

• Blocking of the arterial roads by debris, as currents wash away bridges and vehicles.
• While death and damage to property are the surface manifestation of these rains, there is a range of secondary effects with long-term downstream impacts.
• Schools and transport facilities, for instance, are immediately put out of action, leading to the loss of productive hours.
• Cattle and saplings are left to perish, which in turn destroys livelihoods, debilitates family finances, and strains the finances of the state exchequer.

Why landslides and flash floods are becoming more frequent in the Himachal mountains?

1. Ecological Sensitivity of the Himalayas and anthropological interventions:
   • Mountains in Himachal Pradesh are part of the Himalayan range that are young and fragile, creating cracks and fractures in the rock that could widen in the future and create a rockfall or slope failure zone, a phenomenon in which a slope collapses abruptly under the influence of rainfall or an earthquake.
   • Both Lahaul-Spiti and Kinnaur fall in the Himalayan ranges, known for geological and ecological vulnerability.
   • Environmental activists claim the state’s policy of promoting mega hydropower projects is being implemented in a fragile and eco-sensitive zone, without an appreciation of the cumulative impact of the works.
   • More than 140 hydropower projects have been allocated in the Sutlej basin and disasters like the ones in Chamoli and Kedarnath are in the making.
2. The Bane of Urbanisation, Soil Infiltration Capacity Decreased:
   • Urbanisation has led to a decrease in soil infiltration capacity, resulting in floods.
   • This has led to an increase in the incidence of flash flooding and landslides, making the region very vulnerable to natural disasters.
   • If the landslide comes down to the river stream, it increases the chances of floods.
3. Glacial Retreat due to Climate Change:
   • Higher Himalayas were once home to numerous glaciers, which have now retreated owing to global warming and climate change.
   • Glacier is a moving mass of ice, soil, and rocks and thus, it consists of lots of loose sediments.
   • According to geologists, the retreating glaciers have left behind unlimited sediments that consist of an unstable mix of earth and rocks in the higher reaches of the Himalayas.
   • In such cases, even less rainfall is good enough to move the boulders and debris downstream.
   • Hence, the higher Himalayan region is very unsuitable for dams and tunnels due to the higher concentration of sediments.
   • A recent path-breaking report by the Intergovernmental Panel on Climate Change (IPCC) on the effects of climate change has also flagged glacial retreat in the Hindu Kush Himalayas as a problem.
   • Snow cover has reduced since the early 21st century over high mountains in Asia which include the Himalayas, and glaciers have thinned, retreated, and lost mass since the 1970s as per the IPCC report.

Government interventions:

• Improvement in the system of early warning forecasts.
• The India Meteorological Department now provides fortnightly, weekly, and even three-hourly weather forecasts to districts that provide integrated warnings about flash floods and lightning.
• However, not all of these are accurate, and often, they are not provided early enough for authorities to prepare themselves.
• In recent years, improvements in early warnings for incoming cyclones have helped state agencies evacuate and rehabilitate the most vulnerable, but such success has not been observed for floods.
• Landslide Hazard Zone maps were created for some of the country’s pilgrim routes.
• Geological, topological, and anthropogenic elements are used to define these zones.
• Lithology, soil, slope, drainage, lineament, land use, and other characteristics are among them.
• Currently, pilgrimage routes in Himachal Pradesh, Uttarakhand, and Meghalaya can be found on these maps.

Way Forward:

1. Avoiding the construction of mega hydro-projects in the fragile zone: Higher Himalayas, both climatically and tectonically, are highly sensitive, so much so, that at the first stance the construction of mega hydro-projects should be avoided or else they should be of small capacity.
2. Scientific construction techniques: The construction of roads should be done with all scientific techniques. At present, roads are being made or widened without taking proper measures such as slope stability, good quality retaining walls, and rock bolting. All these measures can restrict the damage done by landslides up to some extent.
3. Listening to Tribals Inhabiting Sensitive Zones: The hills of Himachal Pradesh, Uttarakhand are prone to natural disasters like flash floods, cloudbursts, and landslides. The local people and the youth have been demanding a halt to hydropower development It is high time the government listens to people’s voices.

Conclusion:

• The IPCC has warned that snow-covered areas and snow volumes will continue to decrease during the 21st century, snowline elevations will rise and glacier mass is likely to decline further as emissions rise.
• Rising global temperature and rain can increase the occurrence of glacial lake outburst floods (GLOFs) and landslides over moraine-dammed lakes.
• While the inherent risks of infrastructure development in hills and unstable terrain are well understood, these are often neglected by authorities in the name of balancing the demands of the people for better infrastructure and services.
• The increased risk and cost to such projects and infrastructure should be factored in when they are tendered out by the government, and scientific advice regarding development ought to be strictly followed.

Source: The Hindu

Mains Question:

Q. Why landslides and flash floods are becoming more frequent in the Himachal mountains? Suggest the way forward to preserve the fragile and eco sensitive zone Himalayan zone. (250 words).