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Kedarnath disaster: Facts and plausible causes

Authors:
Dwarika P Dobhal at Wadia Institute of Himalayan Geology
Dwarika P Dobhal
Anil Gupta at Indian Institute of Technology Kharagpur
Anil Gupta
Manish Mehta at Wadia Institute of Himalayan Geology
Manish Mehta
Deen Dayal Khandelwal at Wadia Institute of Himalayan Geology
Deen Dayal Khandelwal
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SCIENTIFIC CORRESPONDENCE
CURRENT SCIENCE, VOL. 105, NO. 2, 25 JULY 2013 171
Kedarnath disaster: facts and plausible causes
Recent climate changes have had signifi-
cant impact on high-mountain glacial
environment. Rapid melting of snow/ice
and heavy rainfall has resulted in the
formation and expansion of moraine-
dammed lakes, creating a potential dan-
ger from dammed lake outburst floods1.
On 16 and 17 June 2013, heavy rains
together with moraine dammed lake
(Chorabari Lake) burst caused flooding
of Saraswati and Mandakini Rivers in
Rudraprayag district of Uttarakhand
(Figure 1 a). Prolonged heavy down pour
on 16 and 17 June 2013 resembled
‘cloud burst’ (except for amount of pre-
cipitation of 100 mm/h) type event in the
Kedarnath valley and surrounding areas
that damaged the banks of River Manda-
kini for 18 km between Kedarnath and
Sonprayag, and completely washed away
Gaurikund (1990 m asl), Rambara
(2740 m asl) and Kedarnath (3546 m
asl) towns. The roads and footpath bet-
ween Gaurikund and Kedarnath were
also damaged. There are reports of loss
of large number of human lives and
damage to the property and livestock.
The Chorabari Lake (3960 m asl) also
known as Gandhi Sarovar Lake is a snow
melt and rain fed lake, located about
2 km upstream of Kedarnath town which
is approximately 400 m long, 200 m
wide having a depth of 15–20 m. The
bursting of this lake led to its complete
draining within 5–10 min as reported by
the watch and ward staff of the Wadia
Institute of Himalayan Geology (WIHG)
who were present in WIHG camp at
Chorabari Glacier on 16 June and early
morning of 17 June 2013. The heavy
rainfall together with melting of snow in
the surrounding Chorabari Lake washed
off both the banks of the Mandakini
River causing massive devastation to the
Kedarnath town. The WIHG meteoro-
logical observatory at Chorabari Glacier
camp (3820 m asl) recorded 210 mm
rainfall in 12 hours between 15 June
(5:00 p.m.) and 16 June (5:00 a.m.)
2013. On 16 June 2013 alone (from
5:00 a.m. to 5:00 p.m.), 115 mm rainfall
was recorded, causing 325 mm rain in
24 hours. WIHG has another rain gauge
installed at its geophysical facility
(MPGO) at Kopardhar near Ghuttu
(30.53°N, 78.74°E; 1836 m asl), which is
approximately 38 km (aerial distance)
from Kedarnath. The Ghuttu rain gauge
recorded 58 mm on 15 June, 121 mm on
16 June and 93 mm on 17 June with no
rainfall on 18 June (Figure 2). The sur-
face atmospheric pressure began to
decrease on 15 June reaching a low
(832.4 mB) on 17 June (Figure 2). Dur-
ing 15–17 June 2013, the heavy rains
also caused devastation in other regions
of Uttarakhand, Himachal and Nepal.
The India Meteorological Department
(IMD) linked heavy to very heavy rain-
fall on the higher Uttarakhand, Himachal
and Nepal Himalaya to the convergence
of the Southwest Monsoon trough and
Figure 1. a, Satellite view of Kedarnath area, showing drainage system, glaciers, lake and township4; b, The India Meterological
Department image (17 June 2013) suggested that the heavy rainfall on the higher Uttarakhand, Himachal and Nepal Himalaya caused
the collision of the monsoon and westerly disturbance. Arrows (red colour) on the map indicate the moisture sources of the area.
(Source: Figure 1 b: http://www.imd.gov.in/section/satmet/dynamic/insat.htm)
SCIENTIFIC CORRESPONDENCE
CURRENT SCIENCE, VOL. 105, NO. 2, 25 JULY 2013
172
Figure 2. Rainfall and atmospheric pressure recorded at Kopardhar observatory near Ghuttu (WIHG), which is
approximately 38 km (aerial distance) from Kedarnath.
westerly disturbances, which led to the
formation of dense cloud over the Utta-
rakhand Himalaya (Figure 1 b).
The Kedarnath temple town is located
in the western extremity of the Central
Himalaya (30°44′6.7″N; 79°04′1″E) in
the Mandakini River valley which has a
total catchment area of ~67 km2 (up to
Rambara), out of which 23% area is cov-
ered by glaciers2. The catchment area is
situated in the glacier modified U-shaped
valley; the altitude ranges from 2740 to
6578 m asl. Such a variation in the alti-
tude provides diverse landscape. Bhart
Khunta (6578 m), Kedarnath (6940 m),
Mahalaya peak (5970 m) and Hanuman
top (5320 m) are few well known peaks
in the area. Mandakini River originates
from the Chorabari Glacier (3895 m)
near Chorabari Lake (Figures 1 and 3)
and joins Saraswati River which origi-
nates from Companion glacier at Kedar-
nath (Figure 3), passing through
Rambara and Gaurikund. The Madhu
Ganga and Dudh Ganga are the main
tributaries that merge into the Mandakini
River at Kedarnath town. Another
equally important tributary of Mandakini
River is Son Ganga which originates from
Vasuki Lake (4040 m asl) and has a
confluence with Mandakini River at
Sonprayag (1709 m asl) which finally
merges with Alaknanda River at Rudra-
prayag.
Geologically, the area north of the Pin-
dari Thrust comprises calc silicate, bio-
tite gneisses, schist and granite pegmatite
apatite veins belonging to the Pindari
Formation3. Above 3800 m asl altitudes,
glacial processes dominate and between
Figure 3. Geomorphological setup of the Kedarnath area and view of settlement of the Kedar-
nath town along the river bank of Mandakini (May 2012 photo).
Figure 4. Histogram of summer rainfall pattern of the Kedarnath area during the period 2007
to 2012 AD. Maximum precipitation occurred during the rainy season from July and August5.
SCIENTIFIC CORRESPONDENCE
CURRENT SCIENCE, VOL. 105, NO. 2, 25 JULY 2013 173
Figure 5. a, The Landsat (8) satellite image (23 June 2013; after disaster), sowing the, lake burst (1), Gulleys erosion/cloud burst events (2)
and circle (3) indicate the site of maximum devastation (http://blogs.agu.org/landslideblog/). b, The panoramic view of Chorabari Lake and Gla-
cier, the red circle indicate the weak zone of the lake, where the lake was burst. c, The photograph showing the maximum devastation in Kedar-
nath town (Photo: Internet). d, Cartosat image (Bhuwan) of post disaster of the Kedarnath and surrounding areas and clearly indicating
Chorabari Lake outburst. The red circle indicates the breaching point of the Lake (http://bhuvan-noeda.nrsc.gov.in/projects/flood/#mappage).
3800 and 2800 m asl glaciofluvial pro-
cesses are dominant; below 2800 m asl
mainly the fluvial processes are active.
Geomorphologically, Mandakini valley
was formed by the erosional and depo-
sional processes of glacio-fluvial origin.
The Kedarnath town is situated on the
outwash plane of Chorabari and Com-
panion glaciers (Figure 3). The channels
of Mandakini and Saraswati Rivers en-
circles this outwash plane and meet near
the Kedarnath town where the outwash
plane ends. These streams cut their banks
every year. Overcrowding of the people
near the temple led to a change in the
course of Sarswati River which now
flows just behind the Kedarnath town
(Figure 3). Downstream near Rambara
and Gaurikund the houses have been
built on the old colluvial or fluvial
deposits which are loose and prone to
landslides and river cuttings.
Rainfall data from an automatic
weather station (installed near the
Chorabari snout) indicates that the Indian
Summer Monsoon is the major source of
precipitation (rainfall) in the study area
with partial contribution from western
disturbances during winter. Winter pre-
cipitation generally occurs between
December and March when the western
disturbances are dominant in the area as
they move eastward over northern India.
Total summer (JJAS) rainfall for each
observation periods between 2007 and
2012 were 1685 mm, 1513 mm, 734 mm,
1662 mm, 1348 mm and 1115 mm for
respective years. Based on the available
rainfall data from our observatory at
Chorabari glacier, the area received
maximum precipitation during the rainy
season, i.e. July and August (Figure 4).
The preliminary results suggest that
the following two events caused devasta-
tion in the Kedarnath area of the Manda-
kini River basin.
Event 1
On 16 June 2013, at 5:15 p.m., the tor-
rential rains flooded the Saraswati River
and Dudh Ganga catchment area, result-
ing in excessive flow across all the chan-
nels. Following this very active erosion
began in all the other gulleys causing ex-
cessive water and sediment accumulation
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CURRENT SCIENCE, VOL. 105, NO. 2, 25 JULY 2013
174
in the major rivers (Figure 5 a). As a
result, large volumes of water struck the
town which simultaneously picked huge
amount of loose sediment en route. The
voluminous water studded with debris
from the surrounding regions and glacial
moraines moved towards Kedarnath
town, washing off upper part of the city
(Sankaracharya samadhi, Jalnigam guest
house, Bharat Seva Sangh Ashram, etc.)
and leading to the biggest ever devasta-
tion we have seen in the region. Our
meteorological stations near Chorabari
glacier recorded 325 mm rainfall at
the base of the glaciers in two days on
15 and 16 June 2013. Due to heavy
downpour, the town of Rambara was
completely washed away on 16 June eve-
ning.
Event 2
The second event occurred on 17 June
2013 at 6:45 a.m., after overflow and
collapse of the moraine dammed Chora-
bari Lake (Figure 5 a and b) which
released large volume of water that
caused another flash flood in the Kedar-
nath town leading to heavy devastation
downstream (Gaurikund, Sonprayag,
Phata, etc.). Our study shows that the
main cause of the Chorabari Lake col-
lapse was torrential rains that the area
received between 15 and 17 June 2013.
Due to heavy rainfall the right lateral
basin of the glacier, which is thickly cov-
ered by snow (>7 feet thick near the up-
per part of lake during field work on 4
June 2013) rapidly melted due to rain-
water allowing large amount of water
accumulation in the Gandhi Sarovar lake
(Figure 5 b). There were no outlets in the
lake, the water was simply released
through narrow passages at the bottom of
the lake. Suddenly millions of gallons of
water accumulated in the moraine dammed
lake within 3 days, which increased their
potential energy and reduced the shear
strength of the dam. Ultimately the
loose-moraine dam breached causing an
enormous devastation in the Kedarnath
valley (Figure 5 a, c and d).
Recently, the risk of natural disasters
has increased in the area as a result of
increasing anthropogenic activities
(Figure 3). This trend is likely to
increase in future as the activities like
pilgrimage, tourism, etc. will increase.
The natural flow paths of the channels
get obstructed due to the construction of
man-made structures that results in de-
viation of the flow from its natural
course. Apprehending the tendency of
increasing urbanization due to increase
in the number of pilgrims, tourists and
other developmental activities in the
area, selection of safe land-use locations
would be a formidable task to accom-
plish. However, the Government has to
take care of these issues in future re-
building of the devastated area, though
the task of rehabilitation of the displaced
population is enormous.
1. Bajracharya, S. R. and Mool, P., Ann. Gla-
ciol., 2009, 50, 81–86.
2. Mehta, M., Majeed, Z., Dobhal, D. P. and
Srivastava, P., J. Earth Syst. Sci., 2012,
121, 149–163.
3. Valdiya, K. S., Paul, S. K., Chandra, T.,
Bhakuni, S. S. and Upadhyaya, R. C.,
Himalayan Geol., 1999, 20, 1–17.
4. Bhambri, R., Bolch, T., Chaujar, R. K. and
Kulshreshta, S. C., J. Glaciol., 2011, 57,
543–556.
5. Dobhal, D. P., Mehta, M. and Srivastava,
D., J. Glaciol., 2013 (in press).
ACKNOWLEDGEMENTS. We are grateful
to the Director, Wadia Institute of Himalayan
Geology, Dehradun, for providing necessary
facilities to carry out the study. We thank Mr
Faram Bhandari, Dhanveer Panwar and Pratap
Singh, Watch and Ward at Chorabari Glacier
Camp (WIHG) for information on Lake burst
and rainfall data collection. We also thank
DST and Ministry of Earth Sciences, New
Delhi for financial support.
Received 5 July 2013; accepted 16 July 2013
D. P. DOBHAL*
ANIL K. GUPTA
MANISH MEHTA
D. D. KHANDELWAL
Wadia Institute of Himalayan Geology,
Dehradun 248 001, India
*For correspondence.
e-mail: dpdobhal@wihg.res.in
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Full-text available
  • Feb 2012
Field geomorphology and remote sensing data, supported by Optical Stimulated Luminescence (OSL) dating from the Mandakini river valley of the Garhwal Himalaya enabled identification of four major glacial events; Rambara Glacial Stage (RGS) (13 ± 2 ka), Ghindurpani Glacial Stage (GhGS) (9 ± 1 ka), Garuriya Glacial Stage (GGS) (7 ± 1 ka) and Kedarnath Glacial Stage (KGS) (5 ± 1 ka). RGS was the most extensive glaciation extending for ∼6 km down the valley from the present day snout and lowered to an altitude of 2800 m asl at Rambara covering around ∼31 km 2 area of the Mandakini river valley. Compared to this, the other three glaciations (viz., GhGS, GGS and KGS) were of lower magnitudes terminating around ∼3000, ∼3300 and ∼3500 m asl, respectively. It was also observed that the mean equilibrium line altitude (ELA) during RGS was lowered to 4747 m asl compared to the present level of 5120 m asl. This implies an ELA depression of ∼373 m during the RGS which would correspond to a lowering of ∼2 • C summer temperature during the RGS. The results are comparable to that of the adjacent western and central Himalaya implying a common forcing factor that we attribute to the insolation-driven monsoon precipitation in the western and central Himalaya.
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Glacier changes in the Garhwal Himalaya, India, from 1968 to 2006 based on remote sensing
Article
Full-text available
  • Jun 2011
Glacier outlines are mapped for the upper Bhagirathi and Saraswati/Alaknanda basins of the Garhwal Himalaya using Corona and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite images acquired in 1968 and 2006, respectively. A subset of glaciers was also mapped using Landsat TM images acquired in 1990. Glacier area decreased from 599.9±15.6 km2 (1968) to 572.5±18.0 km2 (2006), a loss of 4.6±2.8%. Glaciers in the Saraswati/Alaknanda basin and upper Bhagirathi basin lost 18.4±9.0 km2 (5.7±2.7%) and 9.0±7.7 km2 (3.3±2.8%), respectively, from 1968 to 2006. Garhwal Himalayan glacier retreat rates are lower than previously reported. More recently (1990-2006), recession rates have increased. The number of glaciers in the study region increased from 82 in 1968 to 88 in 2006 due to fragmentation of glaciers. Smaller glaciers (<1 km2 ) lost 19.4±2.5% (0.51±0.07%a-1 ) of their ice, significantly more than for larger glaciers (>50 km2 ) which lost 2.8±2.7% (0.074±0.071%a-1). From 1968 to 2006, the debris-covered glacier area increased by 17.8±3.1%(0.46±0.08%a-1) in the Saraswati/Alaknanda basin and 11.8±3.0%(0.31±0.08%a -1)in the upper Bhagirathi basin. Climate records from Mukhim (∼1900ma.s.l.) and Bhojbasa (∼3780ma.s.l.) meteorological stations were used to analyze climate conditions and trends, but the data are too limited to make firm conclusions regarding glacier-climate interactions.
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  • Jan 2009
  • Ann Glaciol
  • 81-86
  • S R Bajracharya
  • P Mool
Bajracharya, S. R. and Mool, P., Ann. Glaciol., 2009, 50, 81-86.
  • Jan 2013
  • J GLACIOL
  • D P Dobhal
  • M Mehta
  • D Srivastava
Dobhal, D. P., Mehta, M. and Srivastava, D., J. Glaciol., 2013 (in press).
  • Jan 2012
  • J EARTH SYST SCI
  • 149-163
  • M Mehta
  • Z Majeed
  • D P Dobhal
  • P Srivastava
Mehta, M., Majeed, Z., Dobhal, D. P. and Srivastava, P., J. Earth Syst. Sci., 2012, 121, 149-163.