Section - 1
WATER AND RELATED
RESOURCES
for some activities like pisciculture,
navigation etc. Both these aspects are
discussed below.
(i)
World's oceans cover about three
fourth of earth’s surface. According to the
UN estimates, the total amount of water on
earth is about 1400 Million BCM(Billion
Cubic Metres), which is enough to cover
the earth with a layer of 3000 metres
depth.
However,
the
fresh
water
constitutes a very small proportion of this
enormous quantity. About 2.7 % of the
total water available on the earth is fresh
water of which about 75.2 % lies frozen in
polar-regions and another 22.6 % is
present as ground water. The rest is
available in lakes, rivers, atmosphere,
moisture, soil and vegetation. The water is
effectively available for consumption and
other uses is a small proportion of the
quantity available in rivers, lakes and
ground water. The crisis about water
resources development and management
thus arises because most of the water is
not available for use and secondly it is
characterised by its highly uneven spatial
distribution. Accordingly, the importance of
water has been recognised and greater
emphasis is being laid on its economic use
and better management.
(Table 1.1 & Chart 1)
Water on the earth is in motion
through the hydrological cycle. The
utilisation of water for most of the users i.e.
human, animal or plant involves movement
of water. The dynamic and renewable
nature of the water resources and the
recurrent need for its utilisation requires
that water resources are measured in
terms of its flow rates. Thus, water
resources have two facets. The dynamic
resource, measured, as flow is more
relevant for most of developmental needs.
The static or fixed nature of the resource,
involving the quantity of water, the length
or area of the water bodies is also relevant
The Static Resources
Rivers
India is blessed with many rivers.
Of the major rivers, the Ganga Brahmaputra - Meghna system is the
largest with catchment area of about 11.0
lakh Sq. Km.The other major rivers with
catchment area more than 1 lakh Sq. Km
are Indus (3.21 lakh Sq. Km), Godavari
(3.13 lakh Sq. Km), Krishna (2.59 lakh Sq.
Km) and Mahanadi (1.42 lakh Sq. Km).
(Table 1.2& chart2)
Water Bodies
Inland Fishery Water resources of
the country are classified as rivers and
canals; reservoirs; tanks, lakes & ponds;
lakes and derelict water bodies; and
brackish water. Other than rivers and
canals, total water bodies cover an area of
about 7.4 m.ha. Uttar Pradesh occupies
the first place with the total length of rivers
and canals as 28.5 thousand km., which is
about 15 % of the total length of rivers and
canals in the country. Other states
following Uttar Pradesh are Jammu &
Kashmir and Madhya Pradesh. Among the
remaining forms of the inland water
resources reservoirs have maximum area
(2.9 m.ha) followed by tanks, lakes and
ponds (2.4 m.ha). Most of the area under
tanks, lakes and ponds lies in States of
Andhra Pradesh, Karnataka, Arunachal
Pradesh and West Bengal. These states
along with Rajasthan, Uttar Pradesh and
Orissa, account for 75% of total area under
tanks and ponds in the country. As far as
reservoirs are concerned, states like
Andhra Pradesh, Gujarat, Karnataka,
Madhya Pradesh, Maharashtra, Orissa,
Tamil Nadu and Uttar Pradesh account for
larger portion of area under reservoirs.
More than 88 % of area under floodplain
lakes and derelict water bodies lies in the
states of Arunachal Pradesh, Assam,
Kerala, Orissa and Uttar Pradesh. Orissa
ranks first as regards the total area of
brackish water and is followed by Kerala,
West Bengal and Gujarat. The total area of
inland water resources (other than rivers
and canals) is, thus, unevenly distributed
over seven states namely Orissa, Andhra
Pradesh, Karnataka, Tamil Nadu, West
Bengal, Kerala and Uttar Pradesh
accounting for more than 64% of the
country’s inland water bodies.
(Table 1.3)
Navigation Waterways
The maximum total length of rivers
Is in West Bengal (4741 Km.) .The total
navigable length is maximum in the state
of West Bengal (4593 Km.) followed by
Orissa.(1544 Km.)
(Table 1.4)
(ii)
The Dynamic Resources
Water Resources of India
The annual precipitation including
snowfall, which is the main source of the
water in the country, is estimated to be of
the order of 4000 BCM. The total volume
of rainfall during 1.1.2006 to 31.12.2006
was 3819 BCM as against 3972 BCM
recorded during the previous calendar year
registering a decrease of about 4%. For
the purpose of seasonal rainfall, country
has been divided into 36 meteorological
sub-divisions out of which only 17 have
positive departure from normal rainfall
during 2006 as against positive departure
in 19 sub-divisions during 2005. There
were
widespread
variations
among
different sub-divisions in terms of rainfall
received. During 1.1.2006 to 31.12.2006
maximum rainfall was recorded in Coastal
Karnataka (386.5 Cm.), followed by
Konkan and Goa (338 Cm.) Kerala (330
Cm.), Andaman & Nicobar (245 Cm.) and
Sub-Himalayan West Bengal and Sikkim
(230 Cm). The rainfall less than 50Cm was
recorded in Rajasthan West and Haryana,
Chandigarh and Delhi. However, total
volume of rainfall in the country during
1.1.2003 to 31.12.2003 at 4057 BCM is still
higher than that during 1.1.2006 to
31.12.2006
(Tables 1.5& Chart 3)
The water resources potential of the
country which occurs as natural run off in
the rivers is about 1869 BCM as per the
estimates of Central Water Commission
(CWC), considering both surface and
ground water as one system. GangaBrahmaputra-Meghna system is the major
contributor to total water resources
potential of the country. Its share is about
59 % in total water resources potential of
the various rivers. The estimated per capita
availability of water works out to 1861
cubic metre (cu.m.) as on 1st March 2008.
Due to various constraints of topography,
uneven distribution of resource over space
and time, it has been estimated that only
about 1123 BCM of total potential of 1869
BCM can be put to beneficial use, 690
BCM being due to surface water
resources. Again about 40% of utilisable
surface water resources are presently in
Ganga – Brahmaputra - Meghna system.
The distribution of water resources
potential in the country shows that as
against the national per capita annual
availability of water of 1820 cu. m. in 2001
the average availability in Brahmaputra
and Barak is as high as 14057 cu. m. while
it is as low as 308 cu.m. in Sabarmati basin
in 2000. Brahmaputra and Barak basin with
7.7% of geographical area and 4.2 % of
population of all the basins in the country
has 31 % of the annual water resources.
Per capita annual availability for rest of the
country excluding Brahmaputra and Barak
basin works out to about 1345 cu.m. Any
situation of availability of less than 1000
cu. m. per capita is considered by
international
agencies
as
scarcity
conditions. Cauvery, Pennar, Sabarmati,
East Flowing rivers and West Flowing
rivers are some of the basins, which fall
into this category.
(Table 1.2 & Chart 2)
Surface Storage
A total storage capacity of about
225 BCM has been created in the country
due to the major & medium projects since
completed.
The
Projects
under
construction will contribute to additional 64
BCM while the contribution expected from
projects under consideration is 107 BCM.
Thus likely storage available will be 396
BCM against the total water availability of
1869 BCM in the river basins of the
country. Maximum storage again lies in
the Ganga Basin, which is far ahead of
other basins. The other basins where the
live storage capacity of the projects (taking
those constructed and under construction)
is high are Krishna, Godavari, Narmada
and Indus.
But if projects under
consideration are also taken into account,
Brahmaputra & Barak basin will occupy the
second place after Ganga Basin. Pennar is
the leading basin in terms of storage
capacities as percentage of average
annual flow. The storage capacities as
percentage of average annual flow exceed
50% for Tapi, Krishna, West Flowing
Rivers of Kutch and Saurashtra, Narmada,
Brahmani and Baitarni basins while for
Ganga basin and Brahmaputra - Barak
Basin, the corresponding figures are 17 %
and 9 % respectively. As the Ganga &
Brahmaputra are the leading basins of the
country in terms of average annual flow,
there is a lot of scope to increase their
storage capacities.
(Table 1.7 and charts 4&5)
Major States like Andhra Pradesh,
Gujarat, Karnataka, Madhya Pradesh,
Maharashtra, Orissa and Uttar Pradesh
together account for about 70 % of total
live storage capacity in the country. The
States of Arunachal Pradesh, Orissa &
Uttar Pradesh account for 72 % of the
total
storage
consideration.
of
projects
under
(Table 1.8)
Publication also gives latest year’s
seasonal observed runoff at CWC sites in
different river basins of peninsular India
namely Godavari, Krishna, East Flowing
Rivers, remaining East & West Flowing
Rivers, Cauvery, Narmada and Tapi. The
statements give station wise details of
catchment area upto that station(wherever
available), and average runoff for monsoon
and non-monsoon periods for the latest
year.
Site-wise details of suspended
sediment load for different basins namely
Godavari, Krishna, Eastern Rivers, Tapi,
Mahi, Sabarmati and other West Flowing
Rivers, Cauvery and remaining East &
West Flowing rivers and Narmada for each
of two seasons i.e. monsoon and nonmonsoon are also included. As the period
of availability of data for different river
systems are not uniform, the information
has been presented for the latest year for
which data are available.
(Tables 1.11 to 1.22)
Ground water
The status of expansion of
Hydrograph network in the country can be
known from the distribution of ground
water hydrograph network stations over the
years.
Distribution of blocks/ talukas/
water-sheds/ mandals according to safe,
semi critical and over exploited has also
been given. The maximum number in
category of ‘over-explioited’ are in the state
of Andhra Pradesh (219) followed by 142
in the state of Tamil Nadu. Number of over
exploited blocks is about 15% of total
blocks in the country.
(Tables1.23& 1.24)
Total replenishable ground water
potential of the country has been estimated
as 433 BCM per year. Basinwise breakup
of ground water is not available.
Among the States, the
highest potential of ground water is in Uttar
Pradesh which mostly lies in the Ganga
Basin.The potential of Uttar Pradesh is 76
BCM/year. Mizoram with 0.4 BCM/year is
at the bottom most position among the
states. Development of Ground Water in
Delhi in percentage is the highest followed
by Punjab. The other States where the
percentage development is more than 50
% are Haryana, Uttar Pradesh, Uttranchal,
Rajasthan, Karnataka and Tamil Nadu.
(Tables 1.25 & 1.26)
Irrigation potential
The total ultimate irrigation potential
(UIP) of the country stands at about 140 m.
ha. The share of Minor Irrigation is higher
by 22.96 m.ha. as compared to that of
Major & Medium Irrigation. Ground Water
contributes more than 79 % of the total
ultimate potential through minor irrigation.
Uttar Pradesh and Bihar are two largest
states in term of potential due to Major &
Medium sector. These two states along
with Madhya Pradesh, Andhra Pradesh
and Maharashtra account for about 54% of
the total ultimate potential of Major &
Medium Irrigation in the country. The
largest UIP for Minor Irrigation (Ground
Water) exists in Uttar Pradesh. Andhra
Pradesh and Madhya Pradesh are two
major states in which potential of Minor
Irrigation (Surface Water) is much higher
than the remaining states. Uttar Pradesh
again occupies the first place among the
states so as to have maximum potential
due to all type of schemes.
(Table 1.27)
The World’s total annual renewable
fresh water supply is estimated to be 48.6
thousand BCM. Brazil and former USSR
have maximum volume of available fresh
water. Bangladesh, Canada, China,
Colombia, Republic of Congo, India,
Indonesia, Myanmar, USA and Venezuela
are other countries whose annual
renewable water supply exceeds one
thousand BCM. To have a better idea of
availability, the per capita series has been
worked out for the years 1975, 2000 and
2025. During this period the population of
world is likely to grow up from 406 crores
to 779 crores. The per capita water
availability in world has gone down by 33
% from 1975 level, in 2000. There is a
large inter-country variation in the figures
of per capita availabilty in the country. In
1975, Iceland had the highest per capita
availability of renewable fresh water which
was 770.5 thousand cu. m, followed by
Congo, Surinam, Guyana and Papua New
Guinea in that order. The availability in
Papua New Guinea was less than half of
the availability of Iceland. Further idea
about the skewness of distribution of water
can be had from the fact that Iceland’s per
capita availability was 64 times the average
world availability in the corresponding
period.
The relative position of these
countries will more or less remain same
over the next 50 years, with per capita
availability in Iceland in 2025 being 66% of
what it was in 1975. The average world
availability, however, in 2025 will be only
half of 1975. On the other end of scale we
have countries like Jordan, Libya, Saudi
Arabia, Singapore and Yemen where per
capita water availability was less than
1/20th of world average in 1975. In a span
of another 25 years i.e. by 2000, the water
availability in these countries reduced to 3
% of the world average, which may further
reduce to 2.3 % in 2025. India’s per capita
availability which was about 25.7 % of
average world availability in 1975, had
declined to about 23.4 % of world
availability in 2000 and is likely to reduce
further to about 23 % of world availability in
2025.
(Table 1.28 & Chart 7)
Irrigation in World
Analysing
the
country-wise
geographical area, arable land and
irrigated area in the World, it is found
that among the continents largest
geographical area lies in Asia which
has
about 24% of
the world
geographic area, about 38 % of world's
arable land followed by North Central
America having about 19 % of world's
arable land. Africa has only 14.2% of
world's arable land. Irrigated area in the
World is about 19.8% of the arable land in
2003. During the same period, about 70%
of world's irrigated area was in Asia. Also
38% of arable land of Asia was irrigated in
2003. United States of America (173.5
m.ha.) has the largest arable land followed
by India (160.5 m.ha.).
(Table 1.29 & Chart 8)
Dams Scenario
India: As per the National Register of
Large Dams containing data compiled up
to April 2002 on 4525 Dams in the Country,
Maharashtra has the maximum number of
dams (1651). Decade wise distribution of
dams indicates that the maximum number
of dams in India were completed during the
decades 1971-80 (1263) and 1981-90
(1186).
World : As per the International Water,
Power and Dam Construction Year Book
2007 the World’s largest dam by volume is
in China (Soufengying – 739 x106 m3) and
the World’s highest dam is in Iran (Jafar –
Mashnadi (Sahid Yaqobi) – 611 meter)
(Tables 1.30 to 1.34 & Chart 9)