Post on 17-Oct-2019
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CHAPTER 3
CONCEPTUAL FRAMEWORK FOR SUSTAINABLE TANK
IRRIGATION SYSTEM MANAGEMENT
3.1 INTRODUCTION
In this chapter, a conceptual framework to implement the
restoration scheme of tank irrigation system for sustainable rural livelihood is
developed based on the reviewed literature in the field of tank irrigation
system management and impact of rehabilitation of tank irrigation system.
Sustainable development was defined in the Brundtland report ‘Our
Common Future’ WCED (1987) as “development that meets the needs of the
present generation without compromising the ability of future generations to
meet their own needs”. Subsequently, many authors have used the term
sustainable development for specific development activities like sustainable
agriculture, sustainable forestry, sustainable energy development, etc.
A single development may be considered successful if it is weighed
against its specific performance criteria. But to achieve sustainability, all the
different aspects of development should be considered simultaneously.
An integrated approach is essential for this study. Many research
organizations and individuals have defined sustainability with regard to
development in agriculture, forestry, land management, etc. The Consultative
Group on International Agricultural Research (TAC/CGIAR, 1988, cited in:
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Prinz, 1998) states that sustainable agriculture is the successful management
of resources of agriculture to satisfy changing human needs while maintaining
or enhancing the quality. Current irrigated agriculture could not be sustained
until there is an improvement in water conveyance system and upgrading the
irrigation efficiency with a drainage system.
The major deficiencies that influence the sustainability of tank
irrigation system are inadequate maintenance, reduction in storage capacity,
heavy seepage losses in the delivery system and poor water management
techniques. There is a pressing need to evolve and implement appropriate
strategies that management be sound on technical, social, institutional and
economic dimensions for sustainable development and management of tank
irrigation systems (Arumugam and Mohan 1997).
Farmers involved in implementing tank rehabilitation have to be
helped to meet their felt needs primarily and their utmost cooperation has to
be earned in carrying out rehabilitation program effectively. There are three
factors that qualify the sustainable development of a system, which are: (a)
survivability; (b) sustainability; and (c) efficiency [l/o]. Survivability refers to
the conditions under which a system yields net profits above a certain
minimum level. Sustainability indicates that if the demand increases then the
net profit must also be increased without causing damage to the system,
which results in the sustainable use of the system. Efficiency refers to the
quantity produced in relation to the input use (output/ input) (Arumugam et al,
1997).
The experience with watershed development under the new
participatory approach in India shows that the immediate results are positive
in terms of rise in water tables, crop yields, employment and income of the
participants (Rao, 2000).
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3.2 WATER RESOURCES
Irrigation tanks are one of the major water and common property
resources in Southern Peninsular India. Declination of irrigation tanks
threatens the agriculture productivity and water availability in the South and
South East Asia especially in Southern Peninsular India and Sri Lanka. The
literature on water resources of tank irrigation system identifies numerous
reasons such as socioeconomic, institutional and physical for the decline of
tank irrigation (Von Oppen and Subba Rao, 1980; Reddy, 1990; Reddy et al,
1993; Janakarajan, 1991; Reddy, 1996; Gireesh et al, 1997).
Historically, the decline in tank irrigation is linked with increasing
population density. Tank degradations can be reversed through appropriate
water conservation and management techniques, which enhance groundwater
recharge, agriculture productivity and poverty alleviation in the rural area in
India. These resources need rehabilitation which is given in a framework as
shown in Figure 3.1.
Tank rehabilitation options that can be used to restore to the
original standards should be given priority. Desilting is an important option.
However, as stated earlier in section 2.5, it has been observed that in a 10 year
cycle, for only 3 years the tanks reach full storage, for five years deficit
storage and for two years the tanks fail. Hence, desilting the tank fully is not
economical as the benefits of desilting will be for only three years with tanks
at full supply. Partial desilting can be done nearer to the lower sluice as well
as around the periphery of the tank water spread area (Palanisamy, 2006).
This type of desilting is suitable for system and non-system tanks. Most of the
tanks do not receive an adequate water supply and the chain systems of tanks
have been almost broken. Hence, there is an urgent need to revive the tank-
chains (tank cascade or chain of tanks) through appropriate modernization
strategies for improving the supply channels connecting different tanks.
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This highlight the needs for taking up modernization works at the
chain-level i.e. by considering the entire hydrological boundary as a single
unit rather than viewing individual tanks as separate entities for new
investment (Palanisamy, 2006).
Community wells should be installed in the tank water spread area to provide some supplementary irrigation to the non-well farmers during critical periods. Again, the farmer’s level of access to resources plays a critical role in the acceptability or appropriateness of the various technologies (John, 2002). If the land is a limiting factor to production, then practices that reduce the land area are unlikely to be embraced. If the labour is limited, then the gender division of labour and the timing of the various activities become critical to the adoption of technologies. And if capital is limiting by considering the traditional practice experiences of the farmers, experts and scientists could develop the appropriate technologies jointly with the people. Siltation over many years generally reduces the tank storage capacity. In the earlier years, farmers used to desilt the tanks using their bullock carts and manual labour with the aim of maintaining the tank storage as well as obtaining manure for their lands.
Presently, it is becoming increasingly difficult to desilt by themselves due to the lack of bullock carts and the reduced spirit of Kudimaramath (community repair work). The Government cannot perform the desilting since it is too expensive to desilt the entire tank capacity. And also, it is difficult to dispose of silts outside the tanks. Partial desilting that helps to restore the original (10%) dead storage could be attempted as part of tank rehabilitation options to increase non-irrigation benefits of tank water particularly in the non-tank-irrigation season. The recharging of wells could also be improved. Partial desilting can be done nearer to the lower sluice as well as around the periphery of the tank water spread area (Palanisamy, 2006). This type of desilting is suitable for system tanks and non-system tanks.
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Figure 3.1 Framework for tank irrigation system degradation issues
and appropriate management and conservation for
sustainable development
Problems of small water storage bodies like irrigation tanks, kulams etc,
Silting and non-maintenance of tanks
Chocking of supply channel
Deterioration of the traditional irrigation institutions Non-maintenance of tanks
Encroachment of foreshore area, catchment area and supply channel
Pollution from industries
Restoration of Water Bodies
Maintaining and repairing of tank bund, sluice and surplus weir and improving supply channel
Desilting of tank bed area
Proper maintenance of tank system through farmers’ participation after modernization and restoration
SustainabilityImproving water storage, increasing ground water level through recharge, preventing encroachment of tank bed area and supply channel etc Silting and non-maintenance of tanks
Social EquityEnsure equity, adequacy and reliability in
water supply.
Economic efficiencyHighest productivity both in agriculture and ecosystem, adequacy and reliability in water supply.
SUSTAINABLE DEVELOPMENT
Issues
Cause
Effect
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In many tanks the supply channels feeding the tanks are heavily
silted, and in several cases they are missing due to the combined effect of
both siltation and encroachment.
Restoration of the supply channels with original capacities will help
capture the run-off water to the tanks. Tank siltation is one of the major
causes for the reduction in the tank storage capacity. This is further
aggravated by deforestation in the tank catchment area, by encroachers for
firewood causing soil erosion during heavy rains. Hence, afforestation has to
be taken up in the catchment area. This is further aggravated by deforestation
in the catchment area, both by encroachers and tank irrigators to be
introduced in the tank.
As per the social forestry programme, the Forestry Department is
planting trees in the tank catchment and foreshore areas. In some cases, the
water spread areas of the tanks are also used for planting the trees and after 10
years the trees will be auctioned off. About 50% of the revenue from the
auction will be given to the local Panchayat (Village level administrative
body), which will be spent on tank and village improvement works.
Supply channel desilting helps to receive the water properly from the
river. Channel desilting also helps in getting the benefit by two ways. The
first one is during rainy seasons. Heavy flows coming from the river may
directly enter the tank and fill it up to its full capacity, which may help the
farmers to achieve high productivity. The recharge of groundwater may also
be at its highest level. The second is during non-rainy seasons. With the sluice
gates closed, water may stagnate in the channel, which can be used for
irrigation by gravity or by pumping. This may also help to recharge the
groundwater.
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3.3 STAKEHOLDER CONTRIBUTION FOR TANK
IRRIGATION MANAGEMENT
Conserved tanks and ponds will serve a long lasting multiple uses
supporting various communities including urban areas. Based on situations,
either conservation or development or both assume significance. The
challenges to conservation and development are technological challenges for
restoration, conservation and development, institutional challenges for
revival, conservation and development, and financial and human resources
challenges for revival and redefining the role of the state, research
institutions, resource institutions and NGOs and the local community
(DHAN, 2002).
The situation, therefore, calls for major changes in governance and
management, activism of the locals, research in engineering and tank fed
agronomy, funding by the governments and donors. The desired changes can
be brought about only when the various stakeholders are brought to a
common platform to share their views on the need for a sustained
management. Presently, the tanks have many stakeholders such as the
Irrigation Department, the Local Panchayats, the Revenue Department, the
Agricultural Department, Forest Department and the local people. The
functions of various stakeholders towards sustainable development of tank
irrigation system are highlighted as on Figure 3.2.
There are many stakeholders in the tank and tank related programs,
of which the Government agencies, farmers and technologists are important.
The Government officials, institutions and farmers should be invited for a
meeting to listen to each others views on the tank systems. The meeting
should focus on the status of tanks, tank fed agriculture, tank improvement,
tank administration and encroachment.
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Figure 3.2 Tank restoration schemes for sustainable management of
tank irrigation
Multi stake holder decision making for restoration of tanks
Technologist
Maximising Tank water Productivity
Techniques of groundwater recharge
Farmers Government
Status of tanks and its improvement needed
Past uses of tanksTank restoration and its need
Awareness Training
Performance support Performance evaluation
Changes in livestock economy, changes in housing facilities, changes in farms and house hold assets, growth of social institution, changes in farm and nonfarm activities, employment opportunities etc.
Productivity (yield) of land, value of land and livestock holding, family income and Employment
Social Development Economic wellbeing Environmental sustainability
Changes in groundwater table Changes in cropping pattern through improved groundwater table
Cause
Effect
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Based on these aspects, an enabling solution has to be decided.
Perspectives of technologists are important, which should get integrated in the
decision making to increase the farm productivity. Recent technologies have
been used to improve the tank irrigation and also they have been used for
maximizing tank productivity, groundwater recharge and other tank services.
Micro-irrigation encompasses drip and sprinkler technologies.
The intended framework considers three key areas as equally
important. Figure 3.2, presents the relationship among the three key network
of active stakeholders (Technologist, Government and Farmers), as well as
the three objectives to be achieved (social equity, economic efficiency and
environmental sustainability). The multi stakeholder involvement in decision
making is very important for achieving all the three objectives.
Different stakeholders are involved in tank irrigation and hence,
any decision towards the tank renovation program should be finalised after a
consultation among the different stakeholders. Encroachments and siltation in
waterspread areas and the supply channels, catchments degradation,
deterioration of the traditional irrigation institutions, improper water
management at farm level are some of the major problems confronting tank
irrigation in the State.
Restoration program is carried out before understanding the general
characteristics about tank system and perspectives of farmers, technologists
and the Government. Integration of stakeholders (Government, farmers and
technologists) in decision making for rehabilitation/restoration/renovation,
modernization and desilting etc., is very important for achieving long term
sustainability. Lacking of any one of the stake holder participation in
decision-making may lead to immediate short-term benefit, but it will lead to
long term unsustainability.
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3.4 RESTORATION SCHEMES OF TANK IRRIGATION
SYSTEMS
Managing tank irrigation systems is a complex phenomenon.
Therefore, its management requires a variety of physical, social and economic
policies and techniques, all aimed at minimizing the adverse consequences of
natural disaster events to improve and enhance the quality of life of the
community. Rehabilitation of tank irrigation systems results in an augmented
supply of irrigation water, better recharge of groundwater, improved quality
of drinking water, increased production and productivity, enhanced
employment opportunities and better well-being of the stakeholder
communities. For a sustainable tank irrigation system management through
development (restoration) programme that the restoration programmes should
be sound on environmental, social and economic dimensions. Any restoration
programme must start with identifying the problems of tank irrigation system
through perspectives of farmers, improvement of the tank water productivity,
groundwater recharge and other tank support services, which should be
collaborated by the perspectives of technologists and finally the government
should allocate the funds not only for infrastructure development but also for
institution building and awareness programmes (Deivalatha and Ambujam,
2010).
Now a complete rehabilitation is not possible due to the fact, that
tanks are very old structures. Certain limited components of rehabilitation
works like partial desilting of tanks, desilting of channels, tank bund
strengthening etc. may be possible to get the expected benefits of agricultural
productivity through increased groundwater recharge. However, the major
stakeholders involved to implement these restoration works have to be made
aware of the expected positive impact. Results of the these restoration works
being the benefit of environmental well being through increased agricultural
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irrigated land, socio economical benefit of food security, productivity of
yield and profitability of farm income and also the investment amount is
financially feasible, which are clearly indicated in Figure 3.3.
Figure 3.3 Restoration schemes for tank irrigation systems
Stakeholders involved in implementation of restoration schemes of tank irrigation
system
Stakeholders of Tank Irrigation System Water user groups, NGO, Technologists and Government officials
Restoration works like partial desilting of tanks, desilting of supply channel and tank bund strengthening etc.
Changes in Groundwater rechargeChanges in well water level Pumping duration of wells, Well yield Changes in irrigated area etc.
Changes in crop yield Changes in farm income Changes in income for landless labours by increasing employment opportunity
Increased water availability
Improved agriculture productivity
Socio Economic Impact
Food security Productivity of crop yield Profitability of farm income
Ecological Impact
Increasing irrigated cropping area and cropping intensity and fodder availability for protecting environmental well being byconserve the basic natural sources of agricultural land and rural water bodies
Financially feasibleInvestment scheme of tank irrigation System
Tank irrigation system management through restoration scheme for Sustainable livelihood
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3.5 IMPACT OF IMPLEMENTATION OF RESTORATION
SCHEME IN TANK IRRIGATION SYSTEM
For a successful and sustainable tank irrigation system
management, it should be protected from the issues of degradation and
maintained for a good production. It should involve the relevant stakeholders
in implementing the tank restoration schemes particularly the community
from problem identification to all levels of planning. It should give combined
benefit for a solution of the restoration project.
For a tank irrigation system to be sustainable through restoration
schemes, multidimensional impacts of ecological, social and economic
benefits all need to be assessed as explained in Figure 3.4. These
multidimensional impacts of the restoration scheme of tank irrigation system
project are studied in detail.
Sustainable benefits of technical measures for ecological impact,
social and economic measures for socio economic impact and economic
feasibility are also studied in detail and the factors indicating the
sustainability of each element are determined.
The conceptual framework outlined here can be applied to
developmental schemes of tank irrigation systems not only in Tamil Nadu but
also elsewhere in the world with similar situations, which will be explored
and explained in the following sections. The overall performances of tank
irrigation system developmental programme have been examined in the state
of Tamil Nadu. It is pointed out that tank irrigation system developmental
activities have made significant positive impacts on bio-hydrological aspects
such as surface runoff water harvesting, production and productivity of crops,
changes in cropping pattern and cropping intensity.
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Figure 3.4 Multidimensional impacts of tank irrigation system
restoration schemes
Multidimensional impact of Restoration schemes of tank irrigation systems
Technical Measures Social Measures
Changes in groundwater recharge
Changes in well water level Pumping duration of wells, Well yield Changes in irrigated area etc
Changes in literacy rate Changes in farms and house hold asset Changes in farm and nonfarm activities Employment opportunity
Ecological Impact
Increasing irrigated cropping area and cropping intensity and fodder availability for protecting environmental well being.
Economic Measures
Socio Economic Impact Food Security Productivity of crop yield
Profitability of Farm income
Changes in crop yield Changes in farm income Changes in income for landless labours by increasing employment opportunity
Increment benefit of crop farm income by cropping area, cropping intensity and crop yield
Investment amount of restoration schemes
Investment Appraisal techniques
IRR Benefit Cost Ratio Pay Back Period Benefit Cost Index
Financial Feasibility
Tank irrigation system management through restoration schemes for Sustainable rural livelihood
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These activities have shown significant positive impact on water
table, recharging wells and employment opportunities for rural people, food
security, water availability for cattle and other domestic purposes etc. The
overall economic impacts have been evaluated in terms of Net Present Value
(NPV), Internal Rate of Return (IRR) and Benefit Cost Ratio (BCR). There is
no single indicator to evaluate the success of tank irrigation system
developmental activities. Hence, a feasible approach may be to compare the
performance of a variety of indicators. Such performance indicators may
reflect the diversity of the project objectives. These include raising agriculture
productivity, recharging groundwater for irrigation and drinking, reducing
productivity of non-cultivable land, increasing cultivable land, creating
employment, promoting collective action and building or strengthening social
institutions.
3.5.1 Evaluation Measures for Tank Restoration Schemes
Technical measures: Some technical measures may include the changes in
groundwater recharge, changes in well water level, pumping duration of
wells, irrigated area, and additional area brought under cultivation and
protecting environmental well beings
Socio economic measures: Socio economic measures are used to evaluate the
restoration schemes of tank irrigation systems. Social measures are changes in
literacy rate, changes in farms and household asset, changes in farm and
nonfarm activities, employment opportunity and food security etc. Economic
measures are changes in crop yield, changes in farm income and changes in
income for landless labourers by increasing employment opportunity are
using for assessing the socio economic impact of restoration scheme for tank
irrigation system management.
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The economic measures are also used to evaluate worth of the
project by comparing the values of goods and services generated or conserved
with the cost for assessing its effect on social welfare need and viability.
There are various undiscounted and discounted measures available to evaluate
the projects (Gittinger, 1982).
The undiscounted measures ignore the time value of money and
simply evaluate the worth of the projects. Discounting measures such as Net
Present Worth (NPW), Benefit Cost Ratio and Internal Rate of Return are
used for this purpose.
Key points from the above frameworks are summarized given in
table 3.1. It was used to know about problems of irrigation tanks, solutions to
siltation and evaluation tools for the impact of restoration of irrigation tanks.
Table 3.1 Summary of key points for conceptual framework for
sustainable tank irrigation system
Sl.no Description
key points for analysis Output for the study Remarks
1 Water ResourcesDeclination of small water bodies like lakes, reservoirs, irrigation tanks etc., threatens agriculture productivity and water availability in the South and South East Asia especially in Southern Peninsular India and Sri Lanka.
Maintaining and repairing of tank bund, sluice and surplus weir and improving supply channel. Partial desilting can be done nearer to the lower sluice as well as around the periphery of the tank water spread area. Proper maintenance of tank system through farmers’ participation after modernization and restoration
Sustainability Improving water storage, increasing ground water level through recharge etc Social Equity Ensure equity, adequacy and reliability in water supply. Economic efficiency Highest productivity both in agriculture and ecosystem,adequacy and reliability in watersupply.
Problems and solution for tank irrigation system
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2 STAKEHOLDER CONTRIBUTIONThere are many stakeholders in the tank and tank related programs, of which the Government agencies, farmers and technologists are important.
Solution for problems of water storage bodies i.e. Silting and non-maintenance of tanks ,Chocking of supply channel, Deterioration of the traditional irrigation institutions Non-maintenance of tanks, Encroachment of foreshore area, catchment area and supply channel and Pollution from industries
Sustainability Social Equity Economic efficiency
Problems and solution for tank irrigation system
3 DECISIONMAKERS FOR RESTORATION SCHEMES
Technologist
Farmers
Government officials
Technologists Maximising tank water productivity and techniques of groundwater recharge Farmers Status of tanks and its improvement needed Past uses of tanks Tank restoration and its need Government officialsAwareness, Training Performance support and Performance evaluation
Social Development Economic wellbeing Environmental sustainability.
Problems and solution for tank irrigation system
4 STAKEHOLDEROF TANKIRRIGATIONSYSTEM Identifying the problems of tank irrigation system through perspectives of farmers, technologists and government
Restoration works like partial desilting of tanks, desilting of supply channel and tank bund strengthening etc. Increased water availability Improved agriculture productivity
Ecological Impact, Socio Economic Impact Financially feasible Sustainable livelihood
Problems and solution for tank irrigation system
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5 IMPACT OF IMPLEMENTATION OF RESTORATION SCHEMEMultidimensional impact of Restoration schemes of tank irrigation systems
Technical Measures Social Measures Economic Measures
Socio Economic Impact• Food Security • Productivity of crop yield• Profitability of Farm income Ecological Impact• Increasing irrigated cropping area and cropping intensity and fodder availability for protecting environmental well being.
Financial Feasibility • IRR • Benefit Cost Ratio • Pay Back Period • Benefit Cost Index
Analysis for sustainability of system after restoration
3.6 SUMMARY
Sustainability means maintaining environmental assets or at least
not depleting them. Rapid depletion of essential resources coupled with the
degradation of land and atmospheric quality indicates that man has not only
exceeded its current social carrying capacity, but actually reduced the future
potential and biophysical carrying capacities by extinguishing essential
natural capital stock (Rwelamira, 1999).
To attain sustainable rural livelihood through restoration schemes
for tank irrigation system, the multi stakeholders have to be involved in
implementing the restoration programme. To achieve sustainable management
of tank irrigation systems for livelihood and the conservation of natural
resources as well as poverty alleviation, there is a need to identify appropriate
technologies for tank irrigation system management that are affordable and