UTTARAKHAND FLOODS & LANDSLIDE
Uttarakhand, the Himalayan state is rugged has a fragile geophysical structure, very high peaks, high angle of slopes, complex geology, variable climatic conditions and active tectonic processes.1. Himalayas formed when the Indian plate collided with the Eurasian plate 55 million years ago. The Himalayas are continuously rising as plate convergence between India and Tibet continues. The collision makes the Himalayas an unstable zone. This triggers earthquakes, fracturing and shearing of rocks, making the Himalayan slopes unstable. The process of formation led to rivers forming gorges through rising mountains. It is in these rivers that huge silt has been deposited. At the same time, steep slopes, cliffs were created, especially in and around the Alaknanda-Bhagirathi systems. All this leads to the Himalayan Mountains slopes to be fragile. To cap it all the westerlies collided with the rising air stream of the monsoons to lead to intense rains
2. During April-June strong westerlies are generally active over the mid-latitudes (areas between the tropics and the polar regions, approximately 30° to 60°lat). In May and June the westerlies, which flooded central Europe, reached and were responsible for very heavy rainfall and flooding in central European nations, such as Germany, Austria and the Czech Republic to the Himalayan states via Afghanistan to collide with the monsoon, triggered deadly rains. Driven by westerlies, western disturbances, swept into the north Indian hilly states around mid-June, where a monsoon-related low-pressure system had already moved in from Bay of Bengal. In general, the monsoon is relatively weaker in the Himalayan region, which is located near the "periphery" or the northern limit of the monsoon that brings up to 80% of India's annual rainfall. When westerlies encounter the monsoon, they stagnate. The westerlies virtually locked on to the monsoon system, the two systems feeding moisture into each other gave rise to intense interaction. While monsoon currents progress from south to northwest, western disturbances move across north India from west to east, driving up pressure. In fact, in some Himalayan areas, the monsoon is activated by western disturbances. The unusual combination of westerlies along with monsoons led to intense upliftment of moisture-laden winds and deadly cloudburst. That caused excessive runoff, triggering landslides and flooding. Such mechanism of excessive rainfall is not unusual for the Himalayan region, nor such type of flooding is unusual as such an event takes place in one or another region of the Himalayas.
3. It was GLOF (Glacial Lake Outburst Flood) that caused Kedarnath floods. Kedarnath floods 2013 were caused by the burst of Chorabari Lake or Gandhi Sarovar. Gandhi Sarovar or Chorabari Lake is located at 3,900 metres is a permanent water body on the side of the Chorabari glacier and has been in existence even in maps of the area from 1962. The glacier is about two km upstream from the Kedarnath temple. The lake is surrounded by hard rock on one side and a lateral moraine on the other. The lake is fed by snow and not by the waters of the Chorabari glacier which has receded over the years. The lake was full to the brim and burst its moraine barrier since there was no natural drainage. That outburst is what caused the most damage on June17 and the tons of sediment and water wreaked havoc down the valley. The over 300 mm of rain recorded on June 15 and 16 accelerated the snow melt into the lake. The rain was too early and too heavy causing this extreme event.
Although floods are natural and are part of the hydrological cycle, and floods must also occur and that they must take place because it cleanses the entire system. But, floods also become a hazard when the hydrological cycle is destabilised and the humans interfere with it without having known the dynamics of nature.
A man made disaster
The recent Uttarakhand floods were more manmade than natural. It was not a natural event or phenomena, it was a man-made disaster. The Uttarakhand floods were caused by many man made events one above another in their intensity of effect.
1. Unplanned growth and rampant felling of forests responsible for this scale of disaster. The Himalayan water divides and slopes have witnessed unprecedented deforestation over a long period. Forest cover depletion has loosened soil, and this leads to frequent landslides. Landslides block the natural flow of water leading to inundation or constriction of the river path. While official estimates say forest cover has increased in the Himalaya, observations and facts do not give credence to this claim. The fact is that forests have been actually diverted for a host of land use activities such as agriculture, human settlements and urban built up area expansion for infrastructure development such as hydropower construction as well as road building. Scientific studies indicate that at the current rates of deforestation, the total forest cover in the Indian Himalaya will be reduced from 84.9 per cent (of the value in 1970) in 2000 to no more than 52.8 per cent in 2100. Dense forest areas, on which many forest taxa (groups of species) critically depend, would decline from 75.4 per cent of the total forest area in 2000 to just 34 per cent in 2100, which is estimated to result in the extinction of 23.6 per cent of taxa restricted to the dense Himalayan forests. Vegetative cover slows the speed of falling rain and prevents soil erosion and gully formation - the precursors to landslides and floods. Dense vegetation, by evapotranspiration, also stops nearly 30-40 percent of rainwater from falling to the ground, thereby significantly reducing run-off. Besides holding the soil together, forests and soil soak water from the rain, release it slowly and prevent water flowing as run-off, So, deforestation brings about slope destabilisation which leads to landslides. The landslide and debris flow downstream add enormous load to the streams causing the valley volume to decrease and spilling of the rivers causing flood.
2. Conversion of Pine to Oak Plantation. These parts of the Himalayas that once boasted of oak forests had turned into pine woods. Oak is an un-exploitable tree for commerce compared to the pine that has a variety of uses. From pine resin to its wood, everything is used profitably by man. Pine is profitable for man but it is not profitable for the Himalayas. The oak is a wonderful tree that in fall over years and decades creates a layer of black subsoil that nourishes the thickest undergrowth one can ever see. These scrubs and brushwood feed on rainwater that seeps down to create an organic whole, a sort of natural masonry that toughens and fortifies the soil against erosion caused even by heavy rainfall. Pine trees, unlike the oak, do not grow leaves, but needles that fall and form a smooth dry bed that does not soak water. This prevents the soil from developing underbrush.
Oaks are not protected by law enforcers. In any case the forest department, comprising no doubt some prized ignoramuses, do not mind this because they watch the pines creep up where once were oaks. Oaks are not protected by law enforcers as it does not ensure that profitability. In order to Green the Himalaya, the forest department greened the Himalayas s all they wanted was a Green cover, irrespective of the type of the tree. Pine is chosen as it spins out more money.
3. Erratic rain pattern which may have been a product of climatic and weather aberrations led to intense bursts of rain first, and then its subsequent slowdowns causes the Himalayan rocks to be loosened flooding of silted rivers. Some recent studies, pointed out that Himalayan ecosystems have experienced faster rates of warming in the last 100 years and more than the European Alps or other mountain ranges of the world. In such a scenario, a faster melting of glaciers is expected with a higher water discharge in the Himalayan rivers.
4. Series of dams have upset ecological cycle and hill slope stability. Construction 70 hydro-electric projects recently, including 37 in high landslide susceptibility zone increases the instability of slopes. Large-scale dam building in recent years has caused massive land use changes with ensuing problems in the Himalayan watersheds. Hydropower and allied construction activities are potential sources of slope weakening and destabilisation. Most downstream damage in otherwise flood-free areas is caused by dams and barrages, which release large volumes of water to safeguard engineering structures. Dam operators often release more water during rains than the carrying capacity of downstream areas, causing floods, increasing erosion and destabilising the base of the slopes further.
5. Pilgrimage are responsible for significant human movement into the Himalaya beyond the region's carrying capacity, whether it is Amarnath in Jammu & Kashmir Kedarnath, Badrinath, Gangotri and Hemkund inUttrakhand. Commercialisation of pilgrimage routes with encroachment on river banks, forests and dangerous slopes increased risks manifold. The heavy pilgrim population has also resulted in the mushrooming of shanty towns, cheap accommodation and numerous ramshackle buildings along river banks. Huge building construction, cheap hotels and individual dwellings at Uttarkashi, on the banks of the Assi and Bhagirathi rivers have been allowed. There is hardly any buffer between the river and the human settlements. While it is important to appreciate the aspirations of the local people and their economic activities, there cannot be a lack of enforcement of land use control laws on the part of local governments and officials.
6. A complete neglect of urban planning has led to settlements coming up in danger areas in Rudraprayag, Joshimath, Chamoli etc. These settlements havent followed a simple rule-‘Where the river has its way, stay out it.’ Whether it was Kosi sometime back, and now Alaknanda or Bhagirathi, the rule applies to all.
7. The illegal sand mining that is so common and rampant both of it has removed the protective cover at the base of the slope increasing its vulnerability to various types of mass movements, landslides and slippages.
8. 3 yrs ago, while auditing hydel projects in Uttarakhand, CAG had warned about severe ecological hazards. Its report ignored.
Suggestions
1. Increasing literacy rate and train the people to rediscover their local wisdom, and civilisation. As a part of literacy, and school education, disaster management course should be included in the school and university curriculum. It is also necessary to train school teachers, selected students, women leaders, health workers and social workers to educate others in measures to prevent or mitigate the natural disasters. Such types of program may convince people to believe that natural disasters are not an act of God, rather it is a product of peoples’ action who lose their respect for environment and natural surrounding. To attain all this, there is the need of the strong political determination, pragmatic policy formulation and quick decision making. It is also needed very much to think on improving road infrastructure without slope destailisation and other alternatives to road transport such as ropeway; improving communication facilities to carry out rescue and relief works effectively and efficiently. In order to prevent inappropriate construction of buildings, the building code should be strictly implemented.
2. Afforestation and Species Composition Change. Planting oak by the removal of pine. The oak is ecologically wonderful because its fall over years and decades creates a layer of black subsoil that nourishes a thick undergrowth. These scrubs and brushwood feed on rainwater that seeps down to create an organic whole, a sort of natural masonry that toughens and fortifies the soil against erosion caused even by heavy rainfall.
3. Independent and serious monitoring of the catchment area treatment plans proposed by Forest Departments with funds from hydropower companies needs to be carried out and reported to the Green Tribunal.
4. Himalayan State governments need to consider imposing high environmental tax on visitors, particularly during summer and monsoon months. Heavily sizing down pilgrim numbers in fragile areas must begin
5. All vulnerable buildings need to be either secured or relocated away from rivers. Governments must impose penalties on buildings structures within 200 metres of river banks.
6. Hydropower policy must consider building fewer dams and prioritise those that have the least environmental and social costs.
7. This increasing variability and intense downpours are consequence of temperature changes and other weather aberrations, due to the capacity of warmer air to hold more water vapour. It happened last year inUttarkashi, it's occurred this year again. It's going to continue to happen, frequently. This raises three issues.
8. Surely adaptation means not just desperate evacuation during and after extreme rains, but preparing for them. Experts suggest prior warning systems are feasible, with reasonable investment. Given there was no warning from the IMD, what technological or administrative improvement do we need to ensure that advance warnings are issued before such future events?
9. Two, that needs not just technology but political will. We need to collectively challenge the callous indifference that most political elites have for the lives and livelihoods of the poor
10. And three, even assuming a best-case scenario of capacity, efficiency and political will, what impacts and devastation are inescapable in a difficult and mountainous terrain? What we are currently experiencing is in a world 0.9°C warmer than pre-industrial temperatures. Due to the lag between carbon emissions and global warming, a significantly warmer world is inevitable, as are more extreme events.
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