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Environment
Groundwater: Manage or Perish
by VK Joshi
The specter of global climate change and erratic rainfall
pattern makes one ponder-how are we going to manage our water? Most of
us remain under a false notion that groundwater in unlimited and we can
keep drawing as much as we need. It should always be remembered that
groundwater is like a bank account. If you keep on withdrawing money
from your account without depositing any, you turn in to red in no time.
Similarly if there is less or no rainfall or if the surfaces of the
habitats are all concretized rain water does not reach the groundwater
reservoirs and the groundwater account turns red.
Less rainfall
mean a drought.
A country like India depends much upon rainfall for a
normal crop. Less rainfall means the entire economy going haywire. Yet
another serious problem that emerges is the severe shortage of
groundwater because it is drawn in excess of availability to meet the
demand of irrigation of crops.
Out of net irrigated area of 58.5
m ha in India, the area irrigated through groundwater accounts for 35.0
m ha (60%) says KD Sharma of National Rain-fed Area Authority, New Delhi
in one of his recent paper in Current Science. Over the years India has
shown remarkable progress in the field of irrigation. Between 1951 and
2007 irrigation from groundwater has risen by 6.3 times. This is mainly
due to various government sponsored schemes for tube-well irrigation,
including highly subsidized rates of power for drawing water for
irrigation. A census of minor irrigation schemes conducted during
2000-2001 revealed that about 80% dug wells and 60% tube-wells were
constructed by the farmers using their own savings. A few states did
provide technical assistance to farmers in drilling the wells. In other
words drawing water from subsurface is now a kind of joint venture of
the government and the farmers.
Is it good for the society in the
long run or should it be further controlled by the government? As said
earlier the availability of groundwater is like money in the bank. In a
normal account the individual knows the balance available after each
withdrawal. Here the situation is different. Groundwater account is like
a joint account where the account holders are like spoiled sons of a
rich father. They squander money, here the society believes that
groundwater is perennial and there is unscrupulous exploitation. The net
annual groundwater availability is 399 billion cubic meters (bcm) says
Sharma. The annual groundwater draft is 231 bcm out of which 213 bcm is
utilized for irrigation and 18 bcm is consumed by the domestic and
industrial consumers.
The scenario is not very bright. This is
mainly because the managers of groundwater (administration of the
states) work in development mode without going in to details of demand
and supply. This has lead to overexploitation and some of highly
productive states like Haryana, Punjab and Rajasthan are now water
stressed. There is overexploitation of groundwater to the tune of 109 to
145%. Whereas there are areas like Bihar, Assam, Chhattisgarh, Jharkhand
and Orissa-all facing crisis have 58 to 82% groundwater which is still
unutilized for irrigation. Other major food grain producing states like
Andhra Pradesh, Gujarat, Karnataka, Madhya Pradesh, Maharashtra, Tamil
Nadu, Uttar Pradesh and Uttarakhand have an annual groundwater draft of
45-85%.
Groundwater is mainstay of the country's food-grain
production. In fact a rapid expansion in the use of groundwater for
irrigation between 1960 and 1980s has increased the crop output by many
folds. Overall the stage of groundwater development in the country is
58% says Sharma. Based upon the groundwater development he divides the
major food grain producing states in to three groups.
Group one
States include Punjab, Haryana and Rajasthan. They along with U.P.
contribute on an average 97% of wheat and 51% of rice to the central
pool. Groundwater development in these areas is more than 100% says
Sharma. The group two states include Andhra Pradesh, Gujarat, Karnataka,
Madhya Pradesh, Maharashtra, Tamil Nadu, Uttar Pradesh and Uttarakhand.
In these states the groundwater utilization ranges between 45 and 85%
and they are able to provide reasonable household food security. Though
these states have 39% net sown area under food grains production, they
produce only 32% quantum of food grains in the country due to a lower
productivity.
According to Sharma the states under group three
which include Assam, Bihar, Chhattisgarh, Jharkhand, Orissa and West
Bengal have a larger number of poorer farmers. There the groundwater is
underutilized to the tune of 58 to 82%. Though the government's policy
and implementation is same for these states too, but the individual
farmer is too poor to butt in his share of money to bore tube wells or
make dug cum bore wells. These regions have been invaded by water
�sharks�. They monopolize extraction and supply of ground water. As such
these areas are able to produce only 22% of the food grain for the
central coffers because only 30% net sown area in these states is
irrigated.
Under exploitation and overexploitation both are bad.
While the Tamil Nadu government has subsidized the power for the farmers
heavily so that they can run their tube wells uninterrupted, the farmers
on the contrary sell their water to the contractors supplying water to
the water starved towns of Tamil Nadu, including Chennai. Not contended
with supplying water, once the well dries up due to excessive pumping,
these farmers extract sand from the bore hole and sell it too for the
skyscrapers to come up. Such malpractices need to be checked sternly.
The rivers of Ganges system have a peculiar pattern-most of them
either supply water to the aquifer or take water from the aquifer. This
give and take continues all along the length of the rivers in the
plains. Excessive drawl of water from the tube-wells affects the flow of
the rivers and vice versa. Rivers have already become a refuse carrier.
Along urban areas municipal and industrial waste is dumped on the river
banks. Surface being sandy and porous, all hazardous chemicals reach the
river water in no time during the rains. From the rivers they travel to
the aquifer and finally to the crops. In this regard the government has
to be extra vigilant, especially in eastern Uttar Pradesh, where the
rivers like Gomti have shown a high arsenic content. Areas fed by the
Ganga River in West Bengal are already notorious for their arsenic
toxicity.
At present Ganges, Brahmaputra and Meghna Basins have
abundant groundwater supply. One needs to carry out a holistic planning
of groundwater development in those areas. Once water efficient the
states will certainly prosper as the irrigation facilities will
drastically improve. While developing irrigation facilities through tube
wells in these areas the recharge of groundwater has to be kept in mind.
Unlike the northern states where excessive drawl has been allowed, which
has made the ground water account turn 'red' in the northeastern states
such mistakes can be avoided. Water demand management focusing on need
based allocation and pricing, involvement of stakeholders, effective
implementation of regulatory mechanisms, capacity building and fostering
a sense of identity are some of the measures suggested by KD Sharma for
sustainable utilization of groundwater in the years to come.
Please remember that our planet has no mechanism to produce water.
Whatever water we have today in any form is a gift from the skies. In
case the rain god stops favoring our urban planet then the future
generations may just perish. It is high time to learn to conserve water.
September 27, 2009
Images under license with Gettyimages.com
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