OPEN FORUM
New Delhi, 10 May 2006
Construction Of Big Dams
IS MASSIVE EXPENDITURE JUSTIFIED?
By Dhurjati Mukherjee
Much controversy has generated in
recent times not just in India
but also globally about the efficacy of big0 dams. Delving into history, it is
a well-known fact that dams and canals were the basis of the growth of
civilization. In recent times, of the
50,000 large dams in the world, 90 per cent were built in the 20th
century and half of those are in China. Experts believe that at least one-third of
those dams should not have been built, taking into consideration the benefits
as also the problems.
While many people benefit from
the water and hydroelectricity provided by dams and diversion projects, the
negative aspects far outweigh the positive ones. Towns and farms have been
starved by huge dams and diversions.
Fishing and wildlife enthusiasts and others mourn the loss of rivers drowned in reservoirs or dried up by
diversion projects. These projects have
also been criticized for using public funds to increase the value of privately-held
farmland of a small segment of the population, whereas other uses may have been
more appropriate.
Most important effect of dam
construction in Third World countries has been
the tremendous amount of displacement that it causes. Apart from the huge costs of construction, in
most cases there is no proper rehabilitation of those displaced, leaving them
in a precarious position. But the outcry
against dams is not only because of this factor as hydrologists believe that
river diversion has grave negative effects.
It has been found and generally
agreed that though hydroelectric power is beneficial, the construction of dams
involve high ecological, social and cultural trade-offs. These include: the reservoir behind the dam
inevitably drowns farmland or wildlife habitats and perhaps towns or land; dams
impede or prevent migration of fish, even when fish ladders are provided and
changing from a cold-flowing river to a warm water reservoir can have
unforeseen ecological consequences.
Also, since the flow of water is regulated according
to the needs for power, dams play havoc downstream – water may go from near
flood levels to virtual dryness and
back to flood levels in a single day.
There is disruption in the natural pattern of erosion and sedimentation,
but above and below dams.
During the last few decades,
several hundred thousand people worldwide have been killed by dam failures.
These resulted from inadequate geologic investigation or poor engineering during
construction. One may mention here the
infamous Vaiont dam disaster in Italy
in 1963 when, due to heavy rains, 10.5 billion cubic feet of limestone tore
loose from the south slope and roared as one intact block downward into the
reservoir, wiping out villages and causing considerable loss to life and property.
In 1992, a national survey in the
United States
classified almost one-third of the
country’s 75,000 dams as hazardous, 10,000 as having high hazard potential and
another 13,500 as having significant hazard potential. Similarly, in India according to a Government assessment,
many damaged and distressed are in
Orissa, Bihar, Karnataka and Gujarat.
Around 188 dams all over the
country have been identified as distressed
with different kinds of weaknesses
including leakages, leading to seepage and in need of concrete grouting or more
serious problems. In others, a flaw in
the design has been detected, especially after the dam was given additional
capacity. About 7.56 million hectares are affected every year on an average, a
little less than half being cropped
land
The Sardar Sarovar dam, which has
generated tremendous controversy in the country, is also being constructed with
high hopes of providing water in dry areas and facilitating power projects. The massive
displacement that is due to take place, specially now because of the increase
in the height of the dam (from 110.64 metres to 121.92 metres) reportedly to
irrigate an additional .6 lakh hectares and generate up to 1450 MW power has
evoked massive protests from all
sections of people and Medha Patkar was recently on a hunger strike.
A certain section of
well-informed people believe that apart from the displacement, the huge costs
involved in constructing the dam may far outweigh the possible
benefits that it may bring about. Questions Medha Patkar, the leader of the
Narmada Bachao Andolan (NBA), and quite rightly, are all the families affected,
at dam height 80 to 111 metres rehabilitated as per the law, so that the
ongoing dam construction continues?
As is well known, Narmada
originates in Amarkantaka in Madhya Pradesh and travels over 1300 km before
emptying into the Arabian Sea at Bharuch. Nearly 90 per cent of the water falls in the
State, which is why displacement is maximum here. Of the 245 villages that will be displaced by
the dam, 177 are in MP. It is also
losing 3700 hectares of forest cover in the submergence. Rehabilitation has till now been done for only a small
segment of the displaced population and if total rehabilitation is to take
place finding suitable alternative land (apart from the costs involved) is
indeed a big problem. Keeping all this
into consideration, there is widespread belief that the benefits of such huge
expenses may not really be worth it.
In China
also, controversies have erupted between environmentalists and dam-building
interests over the construction of the Three Gorges Dam across the scenic stretch of the Yangtze
River. The project is the
centerpiece of the Chinese Government’s effort to industrialize. When completed in 2009, the dam is expected
to be the largest in the world, generating 18,000 MW of electricity and provide
control over disastrous flooding of the river that has already taken 300,000
lives in the 20th century.
More than 1.2 million people, including entire cities, farms, homes and
factories, will be displaced to make way for the 370-mile long (600 km)
reservoir.
Critics have pointed out the
enormous human, ecological and aesthetic costs of the dam and are of the view
that harnessing alternative sources
of electricity would have been cheaper. An international campaign to stop the
dam has prevented funding agencies, like the World Bank, from getting involved
but (unlike India)
Chinese officials have effectively stifled internal criticism and are
proceeding with work on the dam.
Thus from these two projects one
can easily conclude that massive
dams have come in for criticism the world over, specially for populous
countries which are resource scarce.
Obviously the reasons are not difficult to find. Even if all criticisms
are not adhered too, one thing clearly stands out, that proper rehabilitation has to be found, which
means not just providing alternative shelter to the displaced but also avenues
of livelihood for these people so that their normal life is not hampered. Development and better life for the people
cannot be done by sacrificing the interests of the poor and downtrodden.---INFA
(Copyright,
India News and Feature Alliance)
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