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Intersectoral Competition for Water Between Users and Uses in Tamil Nadu-India


Abstract and Figures

Water is a manageable asset for drinking, food creation, and industry, and demand increases as the population increases. Water for irrigated agriculture, industry and domestic needs in India will go up to 1,072, 130, and 102 billion m3 (BCM) by the year 2050. In the state of Tamil Nadu in 2025, water needs for irrigation, domestic, livestock, and industrial sectors will be 52.7, 1.5, 1, and 2 billion m3, respectively, against the available supply of 24.6 BCM of surface water and 23 BCM of groundwater during the same period. A balance between need and supply is often difficult to achieve. By the year 2050, some 60 per cent of the world’s population will live in cities. In India and Tamil Nadu, 38 and 48 per cent of people will live in cities. Tamil Nadu is the second most urbanized state in India with 48 per cent of its population living in cities. This urban push will demand a large share of common water resources and most of the reservoir systems will face increased water demand for non-agricultural purposes, bringing in imbalances with other sectors, namely agriculture. Contrary to mounting demand, it will be difficult to facilitate the growing need for water. Furthermore, there are social and environmental costs in terms of the diversion of water from agriculture to urban uses. The discharge of sewage and industrial effluents also pollutes surface and groundwater, affecting not only human health but also the entire ecosystem. This paper examines the water management challenges in Tamil Nadu, India with respect to meeting future water demands across competing sectors.
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Intersectoral Competition for Water
Between Users and Uses in Tamil
S. Suresh *
Department of Civil Engineering, Sona College of Technology, Salem, India
Water is a manageable asset for drinking, food creation, and industry, and demand
increases as the population increases. Water for irrigated agriculture, industry and
domestic needs in India will go up to 1,072, 130, and 102 billion m
(BCM) by the
year 2050. In the state of Tamil Nadu in 2025, water needs for irrigation, domestic,
livestock, and industrial sectors will be 52.7, 1.5, 1, and 2 billion m
, respectively, against
the available supply of 24.6 BCM of surface water and 23 BCM of groundwater during the
same period. A balance between need and supply is often difcult to achieve. By the year
2050, some 60 per cent of the worlds population will live in cities. In India and Tamil Nadu,
38 and 48 per cent of people will live in cities. Tamil Nadu is the second most urbanized
state in India with 48 per cent of its population living in cities. This urban push will demand a
large share of common water resources and most of the reservoir systems will face
increased water demand for non-agricultural purposes, bringing in imbalances with other
sectors, namely agriculture. Contrary to mounting demand, it will be difcult to facilitate the
growing need for water. Furthermore, there are social and environmental costs in terms of
the diversion of water from agriculture to urban uses. The discharge of sewage and
industrial efuents also pollutes surface and groundwater, affecting not only human health
but also the entire ecosystem. This paper examines the water management challenges in
Tamil Nadu, India with respect to meeting future water demands across competing
Keywords: intersectoral competition, ground water, anicut, river basin, fresh water
Edited by:
ShaMohammad Tareq,
Jahangirnagar University, Bangladesh
Reviewed by:
Venkatramanan Senapathi,
Ton Duc Thang University, Vietnam
Parvin Fahmida,
Jahangirnagar University, Bangladesh
S. Suresh
Specialty section:
This article was submitted to
a section of the journal
Frontiers in Earth Science
Received: 02 February 2021
Accepted: 30 June 2021
Published: 08 September 2021
Suresh S (2021) Intersectoral
Competition for Water Between Users
and Uses in Tamil Nadu-India.
Front. Earth Sci. 9:663198.
doi: 10.3389/feart.2021.663198
Abbreviations: BOT, built operate and transfer; BCM, billion cubic metre; BOD, biochemical oxygen demand; CCWR, climate
crop water requirement; CGWB, central ground water board; CPCB, central pollution control board; DFID, DFID engineering
knowledge and research programme; GDP, gross domestic product; GWEC, groundwater estimation committee; IPCC, in-
tergovernmental panel on climate change; LPCD, liters per capita per day; KM, kilometre; NWP, national water policy of india;
MSMEs, micro, small and medium enterprises department; Mm
, million cubic metre; Mg/l, milligram per litre; MHA, million
hectare; Mld, million litres per day; NABARD, national bank for agriculture and rural development; PWD, public works
department; TDS, total dissolved solids; TMC, thousand million cubic feet; TIIC, tamil nadu industrial investment corporation
Ltd.; TWAD Board, tamil nadu water supply and drainage board; RTPs, rural town panchayats; RWH, rain water harvesting;
UTPs, urban town panchayats.
Frontiers in Earth Science | September 2021 | Volume 9 | Article 6631981
published: 08 September 2021
doi: 10.3389/feart.2021.663198
The Indian irrigation sector utilizes about ninety-three percent
of total water withdrawn and the remaining seven percent is
shared between domestic and industrial sectors. At the time of
Indian independence (1947), the irrigation facilities available
were one-sixth of the cropped area. The governmentsmain
concern was to expand the irrigation infrastructure.
Reservoirs, barrages, and diversion structures were
constructed without thinking about environmental issues. In
the late seventies, the importance of ecological balance was
realized and attention turned to improving the performance of
existing systems. In the eighties, it focused on institutional and
social constraints. By 1987, a National Water Policy of India
(NWP) was formulated and provided guidelines for acquiring,
conserving, and utilizing water resources and the need to
ensure equity and equality. The policy recommends the
involvement of farmers in irrigation management. At the
beginning of the 21st century, it was thought that the
integrated land, water, and human resource management
FIGURE 1 | Location map of Tamil Nadu State. Source: Maps of India.
Frontiers in Earth Science | September 2021 | Volume 9 | Article 6631982
Suresh Intersectoral Competition for Water - India
was ideal for sustainable development and safeguarding the
water resources for the future generation.
Tamil Nadu is the southernmost state of India, delimited by
the Indian Ocean on the south, the Bay of Bengal to the east, and
on the west, north, and east by the states of Kerala, Karnataka, and
Andhra Pradesh, respectively (Figure 1). With a spatial extent of
1,30,058 km
, this state covers 4 percent of the total area of India,
7 percent of the population of India, and 3 percent of the water
resources of India (Census of India 2011). Tamil Nadu has a fairly
high average population density of 429 per km
and is also the
second most urbanized state of India with 48.45% of the
population living in urban areas (Chitra and Laxmi, 2017).
The state has a tropical climate with a temperature of 43°Cin
summer and a minimum of a little lower than 18°C during winter
(Statistical Hand Book 2016-2017). The average rainfall of the
state is 925 mm against the average rainfall of 1,170 mm in India.
Tamil Nadu receives its rainfall from the north east as well as
south west monsoons. A variation in the monsoon has a serious
impact on the economic life and livelihood hood of people,
especially in rural areas. Thus, Tamil Nadu is a decit state
from the point of view of water resources both for irrigation and
drinking water and is dependent on the monsoons very heavily.
The intersectoral competition for water between the users and
uses involves varied resources, including 1) water, 2) land, 3)
human, and 4) livestock. Thus, integrated water, land, human,
and livestock resources management is necessary to avoid
conicts and ensure rational and sustainable utilization of
water resources. Tamil Nadu is one of the more progressive
states in India, and has already achieved more than 95 per cent of
its total water potential, and has implemented several inter- and
intra-state water transfer diversions from existing irrigation
projects (the water transfer from Veeranam tank to Chennai
city by a 250 KM pipeline is the second longest ever and the
longest intra state transfer in India (DFID, 2005)). Tamil Nadu
also undertakes ground water extraction, desalination of sea
water, and cloud seeding, etc., to augment water for domestic
sectors. The crux of the entire problem lies in the successful
implementation and successive follow-up. A host of other factors
are responsible for non-implementation or improper
implementation of meeting the water requirement. These
include a lack of coordination, unimodal, multiple
jurisdictions, mutual exclusiveness, and political motivations.
Vairavamoorthy et al. (2007) outline guidelines for the design
of the urban water distribution systems, especially developing
countries with equitable distribution when the resources are
A climate crop water requirement (CCWR) integrated
framework (Mohan and Ramsundram, 2014) has been
developed. The project studied the inuence of climate
variability on irrigation water requirements in an arid region,
the Manimuthar river basin in India, and found that the irrigation
water requirement is likely to increase by 5% in the time period
from 2010 to 2020. Bitterman et al. (2016) present a conceptual
framework for measuring water security in the context of
rainwater harvesting tanks. Glendenning et al. (2012) focus on
the hydrological impact of rainwater harvesting (RWH) on the
ground water recharge in rural areas of India and emphasize
remote sensing methods and modeling for better assessment and
policy to RWH. Sivasankar et al. (2012) studied the various
physical and chemical characteristics of groundwater samples
from Ramanathapuram, a coastal district of Tamil Nadu, and the
aquifer are severely affected, with a uoride content more than
1.5 mg/L. Therefore, this paper investigates the various water
management challenges in Tamil Nadu, India with respect to
meeting future water demands across competing sectors.
Major Surface Water Resources
The state is drained by 34 river basins with about 54 major
reservoirs and more than 300 medium and small anicuts,
barrages, and diversion structures. Construction of dams,
diversion structures, and barrages are centuries old. The Grand
Anicut (called Kallanai in Tamil, kall stone: Anai dam) was
constructed by the chola dynasty of King Karikalan during the
second century BC. It is possibly the oldest existing structure on
earth still in operation. At present, for convenience, the 34 river
basins are grouped into 17 major river basins (Figure-2). Thus,
almost 95 percent of the surface water potential is brought into
human control by way of the construction of dams and anicuts.
While major dams were constructed during British rule, medium
projects were commissioned after independence. Most of the major
rivers like Cauvery, Pennar, Palar are interstate rivers (Figure 2)
and their ows in the state are dependent on certain mutual
agreements with the neighboring states like Karnataka, Andhra
Pradesh, and Kerala. Rivers are state subjects and therefore there
are often disputes about sharing waters between the states. This
problem is further aggravated when the political party in power in a
state is different from the party that rules at the center. Moreover,
since states have been divided on a linguistic basis, there are a
number of reasons for disagreement.
Groundwater Resources
Having utilized more than 90% of the available surface water
resources, it is necessary for Tamil Nadu to develop its own
groundwater resources, including a more judicious conjunctive
use of its own surface and groundwater. The groundwater
estimation committee (GWEC) constituted by the National
Bank for Agriculture and Rural Development (NABARD) with
the Central Ground Water Board (CGWB, 2000) and
Groundwater wing of the public works department (PWD),
estimated that the groundwater potential in Tamil Nadu is
22,432 Mm
, of which 1,022 Mm
is earmarked for domestic
and industrial water supply requirements (CGWB 2017). The
actual requirement of water supply schemes is 1,057 Mm
for the urban and rural populations. However, these gures,
although indicative of the overall water balance, should be
taken with a great deal of caution, particularly as regards
domestic water supply where spot-specic availability is as
critical as sheer availability. At present, only 61% of the
groundwater has been harnessed and it is still the most
economical, individually managed (private) resource.
Traditionally well irrigation was practiced in the eastern part
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Suresh Intersectoral Competition for Water - India
FIGURE 2 | River basin of Tamil Nadu. Source: PWD, Chennai, Tamil Nadu.
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Suresh Intersectoral Competition for Water - India
of the state. There were open wells and the water was drawn by
draught powered by bullocks. The depth and drawing of
groundwater are directly related to the length and duration of
travel by the bullocks, which helped in sustaining the
groundwater without depriving groundwater from neighbors.
The advent of electrication and use of high-powered pump
sets, improvements in drilling technology, and the subsequent
supply of free electricity for agricultural uses had led to the large-
scale mining of groundwater, leading to dwindling quantities and
deteriorating quality. It should be understood that the availability
of an irreproachable standard constitutes part of the very quality
of human life. The difculties and cost of treating polluted water
and the impossibility, even in the medium term, of rehabilitating
polluted groundwater systems should encourage us to understand
the vital need for maintaining good quality groundwater
resources. The overexploitation of groundwater beyond the
annual recharge into aquifers has already led to this resource
being classied as exploited (CGWB 2017).
From the Table 1 it can be observed that 23 percent of total
blocks experience heavy groundwater extraction, over and above
the recharge, resulting in depletion and seawater ingress in the
coastal aquifer system. By adapting spot-specic articial
groundwater recharge techniques continuously for more than
a decade in Tamil Nadu, it is possible to recharge 3 and 4m thick
sedimentary and hard rock terrains aquifers, respectively, and
additionally, recharge about 375 TMC (Thousand Million Cubic
feet) of groundwater.
The demand pattern of water among the various sectors
(agriculture, industrial, and domestic) has changed (Figure 3)
considerably over the past 100 years. For instance, in 2010 out of
the total water supplied, 90% was utilized in the irrigation sector
as compared to 6% in industry and 4% in the domestic water
sector (Natarajan et al., 2017). In 2020, the water utilized by the
irrigation sector reduced to 60% whereas the water diverted to the
industrial sector was 26%, and in the domestic sector 14%.
Figure 4 represents water demand in Tamil Nadu for 2010,
2020, and includes the projection for 2025 to 2050 (PWD,
Chennai, India).
Agricultural Sector
India tops the list of countries with a large extent of the area
brought under irrigation (total gross irrigated area of 62 MHA)
(ICID, 2018). The state of Tamil Nadu with its limited resources
ranks sixth in India and irrigates about 3.5 MHA (State of Indian
Agriculture, 2016). By 2022 the total potential created under
major and medium irrigation projects is reported at 1.34 MHA
(90% of the assessed ultimate potential of 1.5 MHA) and minor
irrigation potential of 2.20 MHA (91% of the ultimate potential of
2.4 MHA). The net sown area accounts for 42.6% of the total
geographical area of which the net and gross irrigated areas as per
the recent statistics were of the order of 2.4 and 2.9 MHA,
respectively. It is estimated that rice crop consumes more than
45% of the total water that goes into agriculture. The major
sources for irrigation are canals/rivers, tanks, and groundwater.
The traditional utilization pattern of the water resources was one
third each from reservoirs, tanks, and groundwater. Recently, the
pattern transformed and the utilization at present is around 30
percent of reservoir water, 20 percent of tank water, and 50
percent of groundwater, respectively. Agriculture performance
(Ruttan 1965;Gollin et al., 2002) is fundamental to Indias future
economic and social development. Agriculture contributes 30%
of GDP, 60% of employment, and is the primary source of
livelihood in rural areas, which account for 75% of Indias
FIGURE 3 | Water demand in India for 2010 and the projection for 2025 to 2050, by Sector. Source: Ministry of Water Resources, India.
TABLE 1 | Groundwater exploitation level in Tamil Nadu. Source: CGWB 2017.
S. No Classication Exploitation level No of blocks
1 Dark 85100% 89
2 Grey 6585% 86
3 White Less than 65% 211
Total Number of Blocks in
Tamil Nadu
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Suresh Intersectoral Competition for Water - India
population and 80% of its poor and low-income population. The
performance of irrigated agriculture, which contributes 55% of
agricultural output, will be the most important inuence on these
objectives. Therefore, the largest irrigated area in the world is in
India (ICID, 2018).
Domestic Water Sectors
There are 146 Municipalities and 15 Municipal Corporations in
Tamil Nadu (Corporation of Tamil Nadu, 2020;Municipality of
Tamil Nadu 2020). The metro water and the Tamil Nadu Water
supply and Drainage Board (TWAD Board) are responsible for
providing drinking water to the city of Chennai and the rest of the
state, respectively. The drinking water requirement by the total
population of Tamil Nadu by 2020 A.D is only 4.5% (1,055 Mm
both for urban and rural population) of the total assessed
groundwater resource, but every year the city of Chennai and
most other towns face acute water scarcity (Vairavamoorthy et al.,
2007). As the population has grown, freshwater (IPCC et al.,
2014) has become increasingly less available where and when it is
needed. Acute water shortages already have required
extraordinary measures in Chennai, where water was
transported from neighboring places by all modes of transport
ranging from bicycles and trucks to railway tankers, with
distances ranging from a few kilometers to 200 km. In certain
parts of the city, people are forced to pay water tax and water
charges to the government and at the same time, make daily
purchases of drinking water from private vendors for drinking
Industrial Water Sectors
Industry in Tamil Nadu
Tamil Nadu is the second-largest state economy following
Maharashtra state, which has a much larger area and
population. Tamil Nadu is also ranked rst among Indian
states in terms of exports from the special economic zone.
Vision Tamil Nadu 2023 anticipates that an investment of 230
billion United States dollars (Rs. 15 lakhs core) will be invested in
the state before the year 2023 (ENVIS 2020). This includes
investment in projects falling under the manufacturing,
infrastructure, and services sectors. At present, out of 217
infrastructure projects listed in vision Tamil Nadu 2023, 88
projects are under various stages of implementation, with the
implementation of the remaining projects, the milestones
envisaged in vision Tamil Nadu 2023 will be achieved.
Tamil Nadu Industrial Investment Corporation Ltd. (TIIC) is
the rst state-level nancial corporation in the country catering to
the needs of MSMEs. TIIC provides nancial support to major
industrial units such as the sugar, cement, textile, and aluminum
industries. TIIC also has a role in the promotion of industrial
clusters like hosiery in Tirupur textiles and foundries in
Coimbatore, Sericulture and Sago factory in Salam and
Dharmapuri, wind mills in Tirunelveli, Palladam, and
Udumalper, etc. The major industries in Tamil Nadu are
information technology, manufacturing, and engineering
industry, automobile industry, leather industry, paper industry,
chemical, and plastic industry, textile industry, handloom and
power loom industry, sugar industry, and chemical industry.
Industrial Water Demand
In Tamil Nadu, industry is the second-highest consumer of water.
Groundwater has emerged as a preferred source to meet the water
requirement of industries since the surface water supply from
municipal sources is not sufciently guaranteed. The industrial
water demand of Tamil Nadu has been increasing with the pace of
industrial development. Furthermore, the growth of water-
intensive industries is constantly putting pressure on the
industrial demand for water, while the annual growth of the
chemical and construction industry is been 8 percent, the textile
and food industry is 6 percent, and the paper industry is 4
Quantity Dimension
In India, there are no accurate estimates of water consumption by
the industrial sector, but different agencies are recommending the
FIGURE 4 | Water demand in Tamil Nadu for 2010, 2020, and the projection for 2025 to 2050. Source: PWD, Chennai, India.
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Suresh Intersectoral Competition for Water - India
water use value. For instance, according to the Ministry of Water
Resources, India, the industrial sector accounts for six percent of the
total freshwater abstraction while the Central Pollution Control
Board (CPCB) recommends 8 percent (Suresh and Surender, 2011).
However, the world bank estimates that the current industrial use in
India is about 13 percent of the total freshwater withdrawal in the
country and predicts the water demand for industrial uses and
energy production will grow at a rate of 4.2 percent per year in
coming years. The estimates of sectoral water demand in Tamil
Nadu are given in Table 2. The industrial water demand in the city
of Chennai is estimated at around 326 Mld. These estimates reveal
that the industrial water demand is not negligible and will
constantly grow in the coming years.
Rising demand for urban and industrial water supplies poses a
serious threat to irrigated agriculture. Irrigated agriculture faces
two signicant challenges, water shortages and dwindling
nancial resources, in the coming decades. In India, irrigation
investments in the past amount to about 30% of total public
investments after independence. In Tamil Nadu, irrigation
projects have taken 18 percent of total/agricultural
investments. The investment pattern of plan outlays for the
irrigation sector in India during 202021 was 230 million and
it rose to 275 million during 202930 but the percentage
allocation for the same period was 18 and 16 percent,
respectively. Despite these challenges, irrigated agriculture will
provide 70 to 75 percent of additional food grain requirements to
developing countries. This will not be possible without 1)
substantial improvements in the productivity of existing
irrigation schemes, and 2) investment in new irrigation projects.
Population Trends and Explosive Urban
The population of Tamil Nadu as per the 2011 census is 72.1 million
(Census of India 2011) and the total population is expected to reach
85 million in the year 2021AD, out of which 32 million comprise the
urban population and 53 million comprise the rural population
(Figure 5). On a happy note, the substantial decline in the birth rate
could fall further during the coming years. It was 28 per 1,000 during
2012 and 19.2 in 2022 and is expected to reach 15 per 1,000 during
the year 2032. The water demand and supply projections have been
made for agriculture, domestic, industrial and livestock requirements
basin wise (as it would be an appropriate unit for planning any water
resources system). For agriculture demand the cropping pattern,
area sown, and water requirements are taken into account. For
domestic purposes, the existing population in urban areas with a
supply of 90 L per capita per day (lpcd) and rural with a supply of
40 L per capita per day has been taken (National Water Mission
2017). For industrial consumption, the yardstick xed by the
industries department is taken into account and for the livestock
the number of cattle on each river basin is taken and an average
consumption of 80 L per capita per day per cattle. The projection for
future requirements for agriculture is made based on future schemes
to be implemented in the river basins. For the assessment of
domestic water supply, the population projections have been
FIGURE 5 | Population of Tamil Nadu: 19012021, source: Census of India.
TABLE 2 | Estimates of sectoral water demand in Tamil Nadu, India.
2010 2020 2025 2030 2040 2050
Volume in billion cubic meters (BCM)
Irrigation 43.22 49.85 52.7 55.78 60.44 65.6
Domestic 1.0 1.2 1.5 2 3 4
Industry 1.5 1.7 2 2.5 3.5 4.5
Live stocks 0.8 0.9 1.015 1 0.97 0.94
Total 46.52 53.65 57.215 60.78 67.91 75.04
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Suresh Intersectoral Competition for Water - India
made for urban and rural areas. For urban areas, a 30 years 100%
increase is taken. For rural areas, 30% was taken. For industrial
projections, the annual increase of 8% was taken into consideration.
As far as the livestock are concerned no norms for the increase have
been xed and as per the present requirement are taken for the
projection also. From research studies, it was revealed that water
needs during 2025 for irrigation, domestic, livestock, and industrial
sectors are 55.28, 2, 1, and 2.5 billion m
, respectively.
Resources scarcity can exacerbate preexisting tensions or invite new
ones (Tamas. Pal 2003), and water is no exception. Like the oil shock
which the world experienced during the nineteen eighties it would be
water shock for the developing countries in the near future, as the
population increases steadily bringing down the per capita availability
of fresh water as the fresh water resources that are renewed through
theglobalwatercycleisanite natural resource in each country
(IPCC, 2014). Access to water is further complicated by conicts
arising over rights to water in river basins shared by countries or by
states within a country (Williams et al., 2015). In India the river is still
a state subject even though many rivers pass through different states.
Coupled with the political process in which a state ruled by a party
can be different from the party in power at the Center (India) further
complicates river basin management. It would be much prudent to
shift the management of the renewable water resources that exist
within administrative and political borders, as water is more of a
regional resource than a global resource.
The central purpose of water resource development is to meet
demand and supply. This process involves a detailed assessment of
demand both for the present and the future. The natural unit of
water resources development is the river basin. Water resources
systems were created for the task of matching the supply to the
demand for water, in basins or in their sub units. Their traditional
form is a group of structures connected through information links;
these connect all aspects of supply with all aspects of water demand.
Organizations for Irrigation Management
Normally, dual-management irrigation systems are developed in a
top-down approach. The water users in their tertiary unitshave to
follow the technical and institutional innovations made by
technicians. Recent rehabilitation programs have not improved
irrigation as expected, and water users have not yet become
partners in irrigation management. Good irrigation management
appears to be difcult, as conicting interests are normal in irrigation,
and different parties have their own responsibilities.
Management Strategies
Management strategies must be multifaceted rather than
unimodel. It should have macro, micro, and grassroots level
planning followed by effective management of catchment (on
the upstream side) reservoir and the command (downstream
side). The illegal felling of trees and excessive grazing over the
catchment besides increasing runoff brings in silt and sediment
which ends in surpluses to sea. Optimal catchment treatment
would help in a great way in the proper upkeep of the structures
The experience in many developing countries has shown that
the fragmented, command-and-controlapproach to the
management of water resources has failed, both economically
and environmentally. Hence, there is a need to use economic
incentives and scal instruments in achieving economic efciency
in the use of the resource. Furthermore, it is necessary to show
that better economic management of this resource will greatly
assist in improving the environment. Thus, a policy package is
urgently required with a judicious mix of legislation and
regulation, including water tariffs, pollution taxes, efuent
charges, and groundwater extraction charges, and providing
tax benets or investment support for water conservation and
efuent treatment plants.
Water Management Techniques
Surface water is utilized by scientic methods to the extent
possible. Even then, the entire surface water available as
surplus is not effectively and economically used, the surplus
water (Suresh and Somasundaram, 1996;Suresh 2002)ows
into the sea. The T.S. Vijaya Raghavan Committee (The
Hindu, 2014) has estimated that from the seven river basins
(Figure 2) of Tamil Nadu State, about 76.94 TMC of oodwater is
let into the Bay of Bengal in the normal monsoon years.
(Figure 6).
To improve the groundwater potential and quality it has been
suggested that check dams be constructed across the rivers or
need, where the groundwater table is lower than the sea level.
Traditional water management techniques have been neglected
or fallen into disuse and are heading to a further decline in water
storage capacity and consequently surface water ow into the
sea. At present, the coordination between user departments is
not up to the required level. The available water sources may be
grouped for a river basin and various activities may be
monitored. Nothing appreciable is being done to economize
water use at present. The difculties encountered in protecting
the installed capacities and loopholes in the system. Tampering
by the public, unwillingness to pay for water supply, insufcient
qualied staff, paucity of funds, and delegation of powers at
various levels may be considered conducive to the present
Rain Water Harvesting in Chennai City, Tamil Nadu
Chennai is a coastal city, meaning it is always under threat from
seawater intrusion along the coast if more freshwater is extracted.
For instance, in the Minjure and Mouthambedu well elds
located north of Chennai City the fresh groundwater aquifer
has been salinized to a length of about 20 KM from the coast with
a seawater migration rate of 427 m per annum-(Natarajan et al.,
2017)(Figure 7). Indiscriminate extraction in Minjur, the coastal
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Suresh Intersectoral Competition for Water - India
area along the North Sea coast of Chennai has spoiled water
because of overexploitation (CGWB 2017).
This agency has identied that the performance of the existing
schemes is insufcient and that the current state of affairs can be
improved by modernizing the existing irrigation system, which is
dilapidated due to neglect and a lack of maintenance over the
years. In most of the systems, the typical problems are an
unrealistic and poor distribution of water with tail-enders
frequently not getting water and even farmers in the upper
reaches getting only unpredictable supply, and that too does
not necessarily correspond to the agricultural calendar.
Increasing New Investments in Irrigation
Although improving the efciency of existing irrigation schemes
is a must, it is still not sufcient to meet the additional
requirement for food and ber in the next 2 decades. Large-
scale new investments in irrigation schemes will be required for
providing adequate food and ber to meet the objectives of
poverty alleviation and development. During the last decade,
real investment in irrigation schemes has declined as the cost of
new schemes has increased, while the international price of food
grains has declined. Given the large contributions required from
new schemes, concerted efforts are needed, both at national and
international levels, to increase real investments in new
irrigation schemes. Many of the delays in the completion of
water resource projects often become costly and by the time a
revised estimate is sanctioned another price escalation has
already taken place.
Water Resources Consolidation Projects
The prestigious Water Resources Consolidation Project was
carried out at an estimated cost of Rs.1400 crores for
remedying the situation. Its main focus is on institutional
arrangements, operation and maintenance, planning and
management of farmers participation in water conservation
and management, and environmental impact assessment. This
project was also undertaken as part of a major revamping of the
organizational structure of the Public Works
Department (PWD).
In the domestic sector, the use of water for ushing, bathing,
washing, and cleaning can be minimized greatly when
conventional taps are replaced by pressure taps where air at
relatively high pressure is mixed with water to reduce the
quantum water needed. In the industrial sector, a change in the
process from water intensive to less water-intensive and nally to
cent percent recycling of water could make a difference. In the
agriculture sector, efforts to encourage water conservation face
special challenges not encountered with other natural resources. In
much of the world, water is not controlled by market mechanisms
because it is either free or unmetered. Now water is a global
resource that can be traded like coal or petroleum. Often, wasting
water in one river basin is seen as irrelevant to those who live in
another. There is signicant scope for water conservation in
irrigated agriculture. Higher water rates for water intensive
crops such as rice and sugarcane could also encourage farmers
a shift towards other crops such as maize, wheat, and barley, etc.
Since irrigation charges are generally much lower than the value of
water in alternative uses, these low prices do not encourage efcient
water use on the farm. Furthermore, efciency will improve by a
more equitable distribution of water between farmers atthe head of
the distribution system and those at its tail end.
Recycling (desalination) had been tried in coastal districts of
Tamilnadu and could be used only for domestic needs (drinking
water) in the absence of alternate sources, but the technology
available at this date is cost-intensive with the unit cost including
depreciation and debt servicing reported from a pilot plant study
in 201819 of (Rs. 100) $ 1.3 per 1,000 L Moreover, the disposal of
FIGURE 6 | Surplus water from Tamil Nadu river basin. Source: The Hindu (June 23, 2014).
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reject water from the desalination plants is a major problem for
these plants.
Tamil Nadu has limited water resources and draws much for its
drinking water schemes from surface, subsurface in riverbeds,
and groundwater sources. A large number of water supply
schemes draw water from inltration wells located in major
riverbeds. A number of water supply schemes, particularly as
regards Urban Town Panchayats (UTPs) and Rural Town
Panchayats (RTPs), draw water from groundwater sources.
Approximately 0.15 million bore wells tted with hand pumps
also supply water to the rural public.
Status of Water Quality in Major Municipal
Water Supply Schemes
An analysis of data reveals that uoride, nitrate, iron, and Total
Dissolved Solids (TDS) are the critical chemical parameters that
noticeably inuence water quality (Sivasankar et al., 2012). The
Tamil Nadu districts of Dharmapuri, Salem, and Periyar are
severely affected by uoride. The districts of Coimbatore,
FIGURE 7 | Sea Water Intrusion North Sea coast of Chennai-Tamil Nadu. Source (CGWB 2017).
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Madurai, Virudhunagar, and Tuticorin are also affected to some
level. In Dharmapuri District about 54% of the sources are found
to be not potable either in one season or another season. High
seasonal variation renders the same water sources as potable in
one season and not potable in another season. Approximately
10% of the sources in Dharmapuri, Salem, and Erode have high
uoride levels of greater than 3 mg/L. Special attention is needed
in these districts to avoid the problem of skeletal ourish. Cases of
skeletal ourish have already been reported in Salem District. The
level of Nitrate in most of the groundwater sources is becoming a
problem and it has been noted in most of the districts. In the
northwestern parts of Tamilnadu, it is above 60%. Increased
agriculture activities and the application of fertilizers may be
attributed to this phenomenon. Parts of the northern districts are
affected by the high level of iron in the water. It has been observed
that the iron content in any source generally decreases with
continuous use.
High seasonal variation is noted in the level of TDS in
groundwater sources in Tamilnadu. In Coimbatore about 90%
of the water sources become non-potable for no specic season.
With respect to groundwater sources, it is difcult to separately
demarcate the saline areas in the state. The level of TDS depends
on the water level and the depth of the well in various places.
Certain pockets in the districts of Ramanathapuram (Sivasankar
et al., 2012), Tuticorin, Pudukottai, and Coimbatore have a TDS
of more than 3,000 mg/L. In these areas where water quality is a
limiting factor, a change of source or treatment of water to bring it
into a form suited for drinking purposes is required. Rainwater
harvesting on rooftops and construction of percolation ponds
(Figure 8) would result in diluting the groundwater by direct
recharge and thus result in the portability of water.
Factors Affecting Water Quality in
In Tamil Nadu, there are about 4,820 highly polluting industries,
which are called RED category industries. It has also been
reported that out of the 5,059 industries listed as requiring
efuent treatment plants, only 1,114 industries have provided
the same type of efuent treatment plant. The impact of tannery
pollution in the Palar river basin is in alarming proportion. The
tannery efuent having high BOD, Sodium chloride, and
chromium are let into the Palar river which takes water from
inltration wells is having high TDS, contrary to the expected
quality for subsurface water in the river bed. High salinity is also
noted in open well and bore well sources in Vaniyabadi, Ambur,
Ranipet, Wallajah, and other towns in Tiruvannamalai, Vellore,
Ranipet, and Tirupathur district. Dindigul is another district,
which is severely affected by tannery pollution. Due to the
depletion of present water sources and lowering of water levels
in many of the bore wells, it is noted that the groundwater quality
is severely affected. It is natural that when the groundwater level
decreases the traveling time and contact time of water through
soil increases and thus carries more salt with it.
Over exploitation of groundwater, which is frequently used and
transported for urban uses indiscriminately can be easily checked
if land policies are framed for fragmentation and subdivision,
pricing of electricity, limiting the use and spacing of deep bore
rigs, and the long-awaited groundwater legislation. From the
research study, it was revealed that an increase in 1015 per
cent of water use efciency in the agriculture sector would result
in sufcient water availability for urban and industrial uses
without sacricing food production. Drinking water (less than
4 per cent of agriculture water use), which is of the highest
priority, should be supplied through pipelines to the tail and
reaches of the river basins (Ramanathapuram district in Vaigai
basin) from existing reservoir schemes rather than using the local
groundwater beyond the recharging limits.
Livestock reared by almost every household in rural areas are
slowly disappearing as many of the cattle are sent to neighboring
Kerala state for slaughter (cow slaughtering is banned in the
Hindu region). Furthermore, several commercial ventures have
come up recently adding to the concentration of livestock
population, commercial cultivation of fodder, and thereby
bringing in pressures on scarce water resources. This is of
serious note, as a pair of bullocks/cows/goats form a symbiotic
and synergistic relationship with the farming community leading
to sustainable agriculture, but commercialization has resulted in a
greater shift from the existing practices. Efforts in the form of
loans and other incentives should be given to encourage small
livestock holdings.
Increased investment in wastewater treatment and reuse could
yield good returns as the marginal cost of treatment, storage, and
conveyance of puried wastewater for agriculture use will be only
. The introduction of tradable water rights will help
move the water from less productive to more productive use.
Farmers could also sell their water rights to the non-agriculture
sector thus making the irrigation systems more competitive
and challenging. Recently a neighboring Kerala state had
ventured into an issue of bonds to raise capital for
FIGURE 8 | Percolation pondarticial recharge technique. Source:
DFID, 2005.
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implementing water projects. Such a venture could help to
boost the morale of the public and encourage them to invest in
developmental projects.
To increase the level of coordination between various sectors
and implement projects in time and full commitment, a hierarchy
of irrigation cooperatives should be formed at different levels with
user participation for the operation and maintenance of systems.
The placement of water issues in the top ve of their manifestos to
choose a political party to form the government is also a welcome
sign in raising the water consciousness of people. In this regard,
the concept of Built Operate and Transfer (BOT) or the Turn over
the system, has already proved successful in minor irrigation
schemes (Tank projects) and could present a solution for conicts
between users as opposed to uses. If minor changes are made in
improving irrigation efciency, reducing efuent discharges, and
increasing the reuse of water in all sectors, they could help solve
water problems and bring prosperity in the foreseeable future.
The datasets presented in this study can be found in online
repositories. The names of the repository/repositories and accession
number(s) can be found in the article/Supplementary Material.
Ethical review and approval was not required for the study on human
participants in accordance with the local legislation and institutional
requirements. Written informed consent to participate in this study
was provided by the participantslegal guardian/next of kin.
The author conrms being the sole contributor of this work and
has approved it for publication.
The author sincerely thanks the reviewers and Professor Sha
Mohammad Tareq for reviewing this manuscript. The author thank
his daughter Akshaya Suresh, XII Class student, Cluny Matriculation
Higher Secondary School, Salem-7, Tamil Nadu and his wife K. Sathia
Meena, Assistant Professor, Government College of Arts, Salem-7,
Tamil Nadu for their support to write this manuscript. This paper is
dedicated to the fond memory of the author's Master degree guide,
(Late) Dr. M.V. Somasundaram, Professor and Scientist 'F' and his
master degree professor in-charge (Late) Dr. S. Thayumanavan at
Centre for Water Resources, College of Engineering, Guindy, Anna
University, Chennai-600025, Tamil Nadu, India.
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Conict of Interest: The author declares that the research was conducted in the
absence of any commercial or nancial relationships that could be construed as a
potential conict of interest.
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endorsed by the publisher.
Copyright © 2021 Suresh. This is an open-access article distributed under the terms
of the Creative Commons Attribution License (CC BY). The use, distribution or
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copyright owner(s) are credited and that the original publication in this journal is
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... (1.5), (1), and (2) billion m 3 , respectively, compared to the available availability of 24.6 BCM of surface water and 23 BCM of groundwater. A balance between demand and supply is often hard to maintain [6]. ...
... Assess true loss components using the most up-to-date methodologies and compare them to the volume of true losses previously calculated (6). ...
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This study employed a comprehensive technique for the systematic estimate of the water balance in Thenpennaiyaru river basin irrigation systems (TRB-IS) in Tamil Nadu, India. KRP reservoir and Sathanur reservoir in TRB are the primary water sources in the study area. We computed the actual water loss in open canals (e.g., leakage and evaporation). A water balance technique provides for the accounting of various system volume inputs (e.g., water abstraction, imported water, water volume owing to precipitation or surface runoff), authorized consumptions, and water losses in canals and intermediate reservoirs. The proposed methodology enables the evaluation of various water loss components (e.g., evaporation losses, unauthorized uses, metering errors, leakage, and discharges) and the calculation of water loss performance indicators that enable the identification of the most significant water loss problems and provide guidance for managing water losses. The approach is evaluated and implemented using a hybrid irrigation system. Results indicate that Original Research Article Venkatesh et al.; AJAEES, 40(10): 749-758, 2022; Article no.AJAEES.90667 750 discharges in canal systems account for over half of the total volume of water loss, followed by leakage in canals and metering problems. These findings emphasize the need to enhance the everyday operation of these systems and restore their infrastructures.
... Water resource challenges faced by India are considerable and can only be addressed by adopting an integrated approach that considers all uses and sources of water (surface water, groundwater, etc.) from the river basin/hydrologic perspective [1]. This requires sound information and knowledge on the water resource base and its uses, coupled with the availability of appropriate tools for analysis and decision making. ...
... A water crisis can mean being flooded by too much water, or having enough water without the minimum quality needed to use it. A water crisis may also be the lack of water management [1]. The Food and Agriculture Organization of the United Nations indicates that for the year 2030 agricultural production will have to be increased by +80% to fulfill food demand, but it will have to be done without the possibility of increasing water withdrawals by more than +12%, which can be done by reducing spillages along canals [4]. ...
In the present study, canal depth, velocity and weather monitoring sensors are designed and implemented in the field irrigation laboratory, Aditya Engineering College, Surampalem, Andhra Pradesh, India. The depth sensor which is used in this project is HC-SR04 sensor and the velocity sensor is YF-S403. A method of data acquisition and transmission based on ThingSpeak IOT is proposed. To record weather data (i.e., temperature, humidity, rainfall depth and wind speed) DHT11 sensor, ultrasonic sensor and IR sensors are used. The purpose of this project is to evaluate the performance of real time canal and weather monitoring devices. A structure of real time weather monitoring devices based on sensors and ThingSpeak IOT, a design was developed to realize the independent operation of sensors and wireless data transmission can help in minimizing the error in data collection. Arduino UNO is connected with canal depth and velocity sensor to generate the output, similarly NodeMCU is connected with weather monitoring device. The results revealed that observed sensor data showed good results when compared/calibrated with the existing conventional measurement system. In order to decrease the time and to get accurate value, it is recommended to consider the sensors for the proper use and to access weather data easily. The developed device worked satisfactorily with minimum or no errors.
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Intensifying droughts and competing pressures on water resources foreground water scarcity as an urgent concern of the global climate change crisis. In India, individual, industrial, and agricultural water demands exacerbate inequities of access and expose the failures of state governance to regulate use. State policies and institutions influenced by global models of reform produce and magnify socio-economic injustice in this "water bureaucracy." Drawing on historical records, an analysis of post-liberalization developments, and fieldwork in the city of Chennai, Leela Fernandes traces the configuration of colonial historical legacies, developmental-state policies, and economic reforms that strain water resources and intensify inequality. While reforms of water governance promote privatization and decentralization, they strengthen the state centralized control over water through city-based development models. Understanding the political economy of water thus illuminates the consequent failures of the state within countries of the Global South.
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The provision of clean drinking water has been given priority in the Constitution of India, with Article 47 conferring the duty of providing clean drinking water and improving public health standards to the State. The appropriate technology of water supply is affected by the geological, economical and cultural characteristics of the projected area. The first target of water supply technology is to fulfill the needs and reduce the potential of infectious diseases. The integrated development of waterworks is important not only in urban areas, but also in rural areas. After the development of the water supply facilities, the most important issue is the sustainability and to meet the increasing demand with growth of water supply services in order to encourage the willingness to pay of communities. The present paper aims to study about the performance, growth rate and expenditure pattern of water supply in rural and urban areas of Tamil Nadu.
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Rainwater-harvesting tanks (reservoirs) in Tamil Nadu, India support agricultural livelihoods, mitigate water insecurity, and enable ecosystem services. However, many tanks have fallen into disrepair, as private wells have supplanted collectively managed tanks as the dominant irrigation source. Meanwhile, encroachment by peri-urban development, landless farmers, and Prosopis juliflora has reduced inflow and tank capacity. This exploratory study presents a conceptual framework and proposed indicator set for measuring water security in the context of rainwater harvesting tanks. The primary benefits of tanks and threats to their functionality are profiled as a precursor to construction of a causal network of water security. The causal network identifies the key components, causal linkages, and outcomes of water security processes, and is used to derive a suite of indicators that reflect the multiple economic and socio-ecological uses of tanks. Recommendations are provided for future research and data collection to operationalize the indicators to support planning and assessing the effectiveness of tank rehabilitation.
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The natural processes and man-made disturbances in the watershed have influenced the micro climate and in turn affect the hydrology of the watershed along the time scale. The increase in emission of greenhouse gases into the atmosphere might induce variation in climatic pattern in the future. In hydrological models, the climatic parameters remain to be deterministic variables in simulating the surface water or groundwater components. In the recent past, climatological cycle and its variability have been incorporated into water resources systems modeling by many researchers. In this study, an attempt has been made to study the influence of climatic variability on irrigation water requirements in an arid region on a temporal scale, which will help in the water resource planning and management of an irrigation system. A climate crop water requirement (CCWR) integrated framework has been developed to estimate the irrigation requirement in Manimuthar river basin, Tamilnadu, India, incorporating variation in climatic parameters over temporal scale. Based on the existing land use pattern and economic development prevailing in the study area, the most likely climatic scenario has been identified as A1B. From the results, it is inferred that the irrigation water requirement is likely to increase by 5% from 2010 to 2020.
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A study was carried out in the Island and mainland regions of Ramanathapuram District to characterize the physico-chemical characteristics of 87 groundwater samples in Island and 112 groundwater samples in mainland which include pH, EC, TDS, salinity, total alkalinity, calcium hardness, magnesium hardness, total hardness, chloride and fluoride. Heavy inorganic load in majority of the groundwater samples has been estimated due to the salinity, TDS, TH and chloride beyond the threshold level which substantiates the percolation of sea water into the freshwater confined zones. Although the groundwater sources are available in plenty, the scarcity of potable water is most prevalent in this coastal area. The Water Quality Index (WQI) and Langeleir Saturation Index (LSI) have also been calculated to know the potable and corrosive/incrusting nature of the water samples. The statistical tools such as principal component analysis, box plots and correlation matrix have also been used to explain the influence of different physico-chemical parameters with respect to one another among the groundwater samples. The percentage of groundwater samples in mainland was more than that in Island with respect to the acceptable limit of WHO drinking standard, especially in TDS, CH, TH and chloride but the converse is observed in the case of fluoride. About 8 % of the mainland aquifers and 42 % of Island aquifers were identified to have fluoride greater than 1.5 mg/l. The signature of salt-water intrusion is observed from the ratio of Cl/CO (3) (2-)  + HCO(3) and TA/TH. A proper management plan to cater potable water to the immediate needs of the people is to be envisaged.
Agricultural production in India has become increasingly reliant on groundwater and this has resulted in depletion of groundwater resources. Rainwater harvesting (RWH) for groundwater recharge is seen as one of the solutions to solve the groundwater problem. This is reflected in an increase in watershed development programs, in which RWH is an important structural component. Understanding the net effect of these development programs is crucial to ensure that net effect on groundwater is positive both locally and within a watershed. Hence, this review focuses on the hydrological impacts of RWH for recharge at the local (individual structure) and watershed scale in rural areas. Surprisingly little field evidence of the stated positive impacts at the local scale is available, and there are several potential negative impacts at the watershed scale. The watershed scale is underrepresented in the field studies and is mainly approached through modelling. Modelling is seen as a possible tool to extend limited field data and scenario studies can be used to examine potential impacts. However, many past modelling studies examining RWH have either had limited focus or have been based on insufficient data. Development of new modelling tools is needed in combination with increased field data collection. Increased use of remote sensing and advanced statistical techniques are suggested as possible new opportunities. In addition, some evaluation criteria are proposed to assess the local and watershed scale hydrological, and other, impacts of RWH as part of watershed development.
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