INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 6, No 2, 2015

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1 INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 6, No 2, 2015 Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN Snow Avalanche as Disaster in Mountain Environment: A Case of Himachal Pradesh Assistant Professor, Centre of Advanced Study in Geography, Department of Geography Panjab University, Chandigarh vishwa.geoinvader@gmail.com ABSTRACT Snow avalanche is a common phenomenon in high mountain landscapes like Himalayas where the sheer force of the down sliding snow uproot rocks, trees or other material and leave behind a devastating picture of death and misery. Such phenomena occur in areas where rapid accumulation of snow takes place and the most favourable location and situation is the high slopes just after a snow storm or heavy snowfall. This paper examines the spatial and temporal avalanche occurrence in Himachal Pradesh. The analysis shows that frequency and magnitude of snow avalanches in Himachal Pradesh are considerably less disastrous and have limited spatial extent; restricted to the Greater Himalayan region and the northern limits of middle Himalayas. Such events are confined to northern and eastern parts of the state where snowfall is perpetual. The locational distribution also shows that within the study area the most vulnerable areas include Chandra river valley from Koksar to Udaipur in Lahaul & Spiti district; Sangla valley, Karcham-Reckong Peo area and Tinku nullah in Poo area to Namgia in Kinnaur district; Pangi area of Chamba district and the higher reaches around Deo-Tibba of Kullu district. Likewise the impact of avalanches in terms of human casualty is confined to Lahaul & Spiti and Kinnaur districts. Key words: Avalanche, disaster, casualty, spatio-temporal distribution, Himalayas. Introduction An avalanche refers to the sudden downhill movement of a snow mass that may consist of rocks, soil, ice and trees. In general, a snow avalanche means failure of snow-covered slopes. The sheer power of the down sliding snow can uproot rocks, trees or other material that comes in its way. Avalanche occurrence depends upon three basic requirements (a) large volume of snow, (b) sloped surface and (c) a trigger mechanism. Such phenomena occur in areas where rapid accumulation of snow takes place. The slopes, especially between degrees, provide a mode for avalanche movement although gentler slopes can also induce avalanche if snow is sufficiently wet (Hyndman & Hyndman, 2009). The trigger mechanism by increasing the stress induces the downhill movement of snow at a very fast pace. The increase in stress may be due to heavy snowfall in a short span of time, over-burden of snow, wind drifting, removal of base layer, weather conditions, tectonically induced or even human induced reasons. Thus the most favourable location and situation is the high slopes just after a snow storm or heavy snowfall. This paper examines the avalanche occurrence in terms of its spatial and temporal dimensions in Himachal Pradesh. In addition, the incidents of snow storms are included in this study, though they are a different phenomenon and operate as a different mechanism. In terms of frequency and magnitude, snow avalanches in Himachal Pradesh are considerably less disastrous and have limited spatial extent. In Himachal Pradesh avalanches are restricted to Submitted on September 2015 published on November

2 the Greater Himalayan region and the northern limits of middle Himalayas. The higher reaches of the state remain under a perpetual cover of snow for a large part of the year and it is here that avalanches occur. In these areas avalanches occur very frequently but go untraced as these areas are devoid of human settlement. This analysis of avalanche as a disaster is therefore restricted to the inhabited parts of Himachal Himalayas. A very small section of land is available and suitable for habitation therefore the occurrence of avalanche even in lesser frequency and magnitude may cause widespread loss. Such events also lead to the blockade of rivers and thus create temporary reservoirs, the outburst of which leads to damaging flash floods. Chronicles of Avalanches Prior to 1971, the information regarding avalanche occurrence is very limited and therefore the historical reconstruction often presents a patchy picture. The Greater Himalayan areas of the state have historically been prone to avalanche hazard. There are two such recorded incidents, one in 1836 (Government of Himachal Pradesh, 1975) and another in 1863 Harcourt (1871). Although it is difficult to decipher whether events of 1836 was an avalanche or intrusion of advancing glacier that blocked the river resulting in glacial lake outburst flood (GLOF). The other incident was a lethal snow storm that killed seventy two people in The gazetteers of Kangra District refer to series of avalanches in Kullu district where Phojal nullah near Manali was blocked and resultant flash flood devastated the downstream valley (Punjab Government, 1917, p. 19). Chander (1989) mentioned 9 events of avalanches in Kullu valley during Since 1971, a number of damaging avalanche events has struck the state. There were six devastating incidents of avalanche during Two porters got killed near Deo-Tibba at a height of 17,000 feet in an avalanche following heavy snowfall on 28 October 1972 while two climbers were killed in 1973 near Manali area and two more died at Arrang village of Lippa valley in Kinnaur district in There were two incidents of avalanche, first occurred in Pangi valley of Chamba district while other incident took place at Sagnam village in Pin valley of Lahaul & Spiti district in the end of March The official records state that these avalanches claimed 30 lives in Lahaul & Spiti district in 1978 (Government of Himachal Pradesh, 2006). The worst incident of avalanche occurred in the tribal district of Lahaul & Spiti during the winter of On 8 th March 1979, about 75 persons were killed in devastating avalanches that occurred in different parts of Lahaul valley. The destruction continued for many days and as many as 237 people lost their lives in Lahaul valley (Government of Himachal Pradesh, 2006). There were two incidents of snow-storm one at Shimla in 1971 and other near Manali in 1977 where two people died. The avalanche information extracted from newspaper archive of The Tribune reveals that there were six incidents of avalanches during 1980s; two were in 1982, one in 1983, two in 1984 and one in These events claimed 21 lives out of which eleven were in Kinnaur, seven in Kullu and three in Chamba district. Besides these events, three incidents of snowstorm in 1981, 1982 and 1987 were reported claiming 21 lives out of which 7 were in Kullu, 9 in Shimla and 5 in Lahaul & Spiti districts, respectively. Seven incidents of avalanches occurred in 1990s, out of which five were in Lahaul & Spiti, and one each in Kullu and Kinnaur districts. All, except the one that hit the Kullu district near Rohtang pass in August, occurred during the winter months. There was at least one avalanche every year 1579

3 except 1990, 1993, 1994 and These events claimed 17 lives, 15 in Lahaul & Spiti and 2 in Kullu district. This next decade recorded 15 events of avalanches in the state. In March 2002, avalanches killed 3 people in Namgia, Skiba and Nippa villages of Kinnaur district while in another incident at Tinku nullah blocked the river that created a huge lake. A huge avalanche struck four villages of Bharmaur in March During January 2006 avalanches damaged apple orchards in Kalichho village of Pangi valley and Nichar and Sangla valley of Kinnaur district. A series of avalanches struck the high altitude areas of Kinnaur, Lahaul & Spiti and Kullu districts in January In Kinnaur district avalanches struck on Sangla-Karcham road and Poari area causing damage to roads, houses and orchards. Two persons were killed in the Allain and Duhangan power project site at Prini near Manali. Another two persons were killed near the Surtang nullah near Sissu village and seven persons buried near Bharatpur in Lahaul & Spiti district. Apart from these events, three incidents of snow-storm occurred in the state. Shimla town was hit by a storm in January 2004 while Chitkul, Rakchham, Saring and Barseri areas of Sangla valley in Kinnaur were badly hit in January In another incident, a snowstorm near Rohtang at Rani Nala area of Kullu claimed 8 lives on 20 November Spatio-temporal distribution and concentration patterns Avalanche as a disaster in Himachal Pradesh is neither very frequent nor an annual feature; however a small but negligible increased has been observed in the overall frequency of avalanche incidence. The occurrence was however limited to just 20 years while no event was reported in 19 years (figure 1). The number of years of avalanche occurrence per decade was 5, 4, 6 and 5 during 1970s, 1980s, 1990s and 2000s, respectively. The period recorded 41 incidents of avalanche in the inhabited parts of the state. There were 13 events of avalanche during 1970s which accounts for per cent of total occurrences during The proportion is and per cent for 1980s and 1990s while in 2000s it increased to per cent (table 1). The occurrence is confined predominantly to winter months from January- March which accounts for over 92 per cent of total avalanche events (table 1). The distribution of avalanches in the state reveals that this hazard is expectedly restricted to four districts situated in the northern part of middle Himalayas and the Greater Himalayas. These include the districts of Kinnaur, Lahaul & Spiti, Chamba, and Kullu which are vulnerable to such hazard (map1). Lahaul & Spiti district is the most vulnerable district where a total of 17 (41.46%) events have occurred during while Kinnaur (36.59%) is the second leading district. Kullu and Chamba account for about 12 and 10 per cent, respectively, of total avalanche events that occurred during the period (table 2). Avalanches were most prevalent in Lahaul & Spiti district during 1970s and the district accounted for nearly 77 per cent of total occurrences in the state. The avalanches were evenly distributed in Kinnaur, Kullu and Chamba district in 1980s while no such event recorded in Lahaul & Spiti. The phenomenon was again concentrated in Lahaul & Spiti during 1990s and in Kinnaur in 2000s and they accounted for over 70 percent of total decadal events of avalanches (table 2). The intra-district analysis shows that avalanche incidents were largely concentrated for particular time period in different districts, e.g. in Lahaul majority occurred in 1970s; Chamba in 1980s; Kinnaur in 2000s while in Kullu district these were almost evenly distributed for every decade (table 3 & map 1). 1580

4 Figure 1: Avalanche occurrence & trend ( ) Table 1: Himachal Pradesh: distribution of avalanche ( ) Pre- Post- Winter Monsoon Monsoon Monsoon Decade Jan-Mar Jul-Sept Decadal Total (per Apr-Jun Oct-Dec cent) (31.71) (14.63) (17.07) (36.59) Total (per 38 (92.68) 0 2 (4.88) 1 (2.44) 41 (100.00) Source: compiled by the author from daily newspaper The Tribune and other sources for the Table 2: Himachal Pradesh: decadal distribution of avalanche ( ) District Total 1 Lahaul & (71.42) 2 (13.33) 17 (41.46) 2 Kinnaur 1 (7.69) 2 (33.33) 1 (14.29) (36.59) 3 Kullu 1 (7.69) 2 (33.33) 1 (14.29) 1 (6.67) 5 (12.19) 4 Chamba 1 (7.69) 2 (33.33)) 0 1 (6.67) 4 (09.76) Total 13 (100) 6 (100) 7 (100) 15 (100) 41 (100.00) Table 3: Himachal Pradesh: intra-district decadal distribution of avalanche ( ) District Total 1 Lahaul & (29.41) 2 (11.77) 17 (100) 2 Kinnaur 1 (6.67) 2 (13.33) 1 (6.67) (100) 3 Kullu 1 (20) 2 (40) 1 (20) 1 (20) 5 (100) 4 Chamba 1 (25) 2 (50) 0 1 (25) 4 (100) 1581

5 Total 13 6 (14.63) 7 (17.07) (100) 4. Human casualty and destruction Figure 2: Avalanche Location and frequency In terms of human casualty avalanches claimed 301 lives during last four decades. There are few events which were very disastrous and claimed several human lives (table 4). Out of the 301 deaths caused by avalanches 269 (89.37%) were in Lahaul & Spiti district. In other three districts less than six per cent people lost their lives to avalanches (table 5). District wise decadal breakup shows that 1970s was the worst hit decade that accounts for 249 (82.72%) out of 301 deaths due to avalanches and 245 deaths were in Lahaul & Spiti district alone. For rest of the decades, the number of casualties remained comparatively low but consistent. For Kinnaur, Kullu and Chamba, 1980s was the most devastating decade. Lahaul & Spiti remained the most vulnerable district except 1980s when over half of the deaths due to avalanches were in Kinnaur district while one-third deaths occurred in Kullu district. 1582

6 Date (DMY) Table 4: Himachal Pradesh: major avalanche events ( ) Location/ Site Description of of Occurrence Avalanche Damage Sangnam, Pin valley, Lahaul & Spiti Lahaul Valley, Lahaul & Spiti 6 persons including 2 women and 4 children were killed and 2 houses destroyed. 75 persons killed in devastating avalanches in Lahaul valley. 40 persons died in the villages Udaipur, Hansa, Bardang, Shakoli. 12 people received injuries. Three villages, Warring, Gardung, Ley Gardung, 9 K.M. from Keylong were completely razed. The death toll in the district reached to 200. A dispensary and a Sarai attached to famous Trilokinath temple in Udaipur area were also destroyed Kilba, Kinnaur 8 killed in an avalanche at Kilba village Udaipur, Lahaul valley, Lahaul & Spiti Piaso Village, Keylong, Lahaul & Spiti Bharatpur, Lahaul & Spiti 9 persons including 5 children killed in an avalanche that occurred at mid-night in Purti village on Sansari-Killar-Thirot road. 6 family members died in avalanche in Piaso village, 7 km from Keylong. 7 persons killed in an avalanche at Bharatpur nullah, while 12 trekkers went missing in the Chandertal area. Table 5: Himachal Pradesh: Decadal Casualty by Avalanche ( ) District Total Casualty Casualty Casualty Casualty (Per cent) 1 Lahaul & (89.37) 2 Kinnaur (5.32) 3 Kullu (4.32) 4 Chamba (0.99) Total (6.98) 17 (5.65) 14 (4.65) 301 (100) 5. Conclusions Avalanches in Himachal Pradesh have restricted spatial, seasonal and temporal extent. Such events remain confined to northern and eastern parts of the state where snowfall is perpetual. These include Lahaul & Spiti, Kinnaur, Kullu and Chamba districts, the first two being the most vulnerable. The locational distribution also shows that within these four districts the most vulnerable areas include Chandra river valley from Koksar to Udaipur in Lahaul; Sangla valley, Karcham-Reckong Peo area and Tinku nullah in Poo area to Namgia in Kinnaur district; Pangi (Tissa) area of Chamba district and the higher reaches around Deo-Tibba of 1583

7 Kullu district (map1). The occurrence is restricted to a limited part of year i.e. winter months of January to March. The temporal expression is highly erratic as well, as evidenced from the fact that avalanche occurrence is highly concentrated to very few years. Likewise the impact of avalanches in terms of human casualty is confined to Lahaul & Spiti and Kinnaur districts. Although the occurrence and human impact of avalanches are lopsided and limited over time and space, the disastrous manifestation possibly will be colossal in light of the fact that the areas most vulnerable to avalanches are also the locations where large scale developmental activities in terms of infrastructure and tourism are taking place. 6. References 1. Chander A., (1989), Landslide: An Expression of Man-Nature Interaction in the Western Himalayas, Unpublished Ph.D. thesis submitted at the Department of Geography, Panjab University, Chandigarh. 2. Government of Himachal Pradesh, (1975), Himachal Pradesh District Gazetteers, Lahul & Spiti, Chandigarh: Greater Punjab Press. 3. Government of Himachal Pradesh, (2006), State of Environment Report, Himachal Pradesh, Shimla: State Council for Science Technology and Environment. 4. Harcourt A.F.P., (1871), On the Himalayan Valleys: Kooloo, Lahoul, and Spiti. Journal of the Royal Geographical Society of London, 41 pp Hyndman D. and D. Hyndman, (2009), Natural Hazards and Disasters, 2 nd edition. USA, Belmont: Brooks/Cole. 6. Punjab Government, (1917), Punjab District Gazetteers, Vol. 30 A, Kangra District, Lahore: Government Printing, Punjab. 1584