Uttarakhand disaster was result of extreme rains and haphazard development: report5 Comments

Author(s): Soma Basu   @sbasu_in Date:Jul 15, 2013

National Institute of Disaster Management suggests guidelines and action plans for

development activities after compilation of comprehensive data

It is believed that a

combination of events caused the devastation in Kedarnath town. A massive landslide occurred upstream in

the north-east region of the Kedar valley. At the same time heavy rainfall formed a small lake in the north-

west of the valley. The debris from the landslide and water from the lake travelled down the slope,

channelled into the glacier, and came down to Kedarnath town (Photo by Rohit Dimri)

The National Institute of Disaster Management (NIDM), in one of its first reports on

the Uttarakhand floods, has blamed “climatic conditions combined with haphazard

human intervention” in the hills for the disaster.

Surya Prakash, associate professor of NIDM, travelled over a 1,000 kilometres in

flood- and landslide-hit areas of Uttarakhand between June 22 and 24 to prepare the

report. He says that the abnormally high amount of rain (more than 400 per cent) in

the hill state was caused by the fusion of Westerlies with the monsoonal cloud

system. Heavy precipitation swelled rivers, both in the upstream as well as

downstream areas. Besides the rain water, a huge quantity of water was probably

released from melting of ice and glaciers due to high temperatures during the month

of May and June. The water not only filled up the lakes and rivers that overflowed but

also may have caused breaching of moraine dammed lakes in the upper reaches of

the valley, particularly during the late evening on  June 16 and on June 17, killing

about several hundred persons; thousands went missing and about 100,000 pilgrims

were trapped.

Prakash says that the Alaknanda river and the Mandakini, both tributaries of the

Ganga), occupied their flood ways and started flowing along the old courses where

habitations were built over time (when the river had abandoned this course and

shifted its path to the east side). Thus, the rivers destroyed the buildings and other

infrastructure that came in its way.

He explains that geomorphological study of the area indicates that the surface

slopes consist mostly of glacial, fluvio-glacial, or fluvial materials, which are mostly

unconsolidated and loose in nature. The drainage studies indicate a migratory or

shifting nature of the river systems that causes aggradations on the concave end of

the river and degradation or toe erosion on the convex part of the river. Due to

morphological setting of the area, the river has high sinuosity and hence, high level

of erosive capacity, especially when it is loaded with sediments (the erosive power of

river with sediments is almost square of the erosive power without sediments).

Damaged houses in

Govindghat. The NIDM report says that the Alaknanda and the Mandakini caused much destruction

because they returned to their old course where buildings were constructed over period of time (Photo by

Indresh Maikhuri)

“The area has been denuded to a great extent due to deforestation and tree cutting

for road construction, and other activities such as building construction, mining and

hydel projects. It has also resulted in increased surface flow and rise of river bed due

to disposal of debris in the rivers,” the report said. Geologically, the rocks in this area

are found highly deformed, degraded and dissected by structural discontinuities and

drainages.

Seismo-tectonically, the area is traversed by several lineaments, faults and thrusts,

which are considered to be geodynamically active. The area had suffered an

earthquake on March 29, 1999 (M-6.8), which caused loosening of rock masses,

ground cracks and landslides, besides killing more than a 100 people due to collapse

of buildings. Thus, the natural terrain conditions combined with climatic/weather

conditions and haphazard human intervention made a conducive environment for

such a hazardous process to take place in this valley, said Prakash.

“The hazard turned into a major disaster when people along with their properties and

infrastructure occupied such areas without adequate information, knowledge,

awareness and preparedness against the potential disaster,” he added.

The main objective of Prakash's visit to the affected areas was to observe the major

damages along the national highway from Rishikesh to Chamoli and interact with

people, including victims, relief workers and local people to learn about the event

and its impacts.

Based on the field observation, Prakash has suggested terrestrial, meteorological

and anthropogenic data with particular focus on landslides, rainfall and other

information relevant to the event should be collected and compiled. “Necessary

guidelines and action plans for tourist/pilgrimage places and hotels,lodges and guest

houses should be developed keeping in mind the concentration of people at such

locations during the time of disasters,” he says.