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1. International Journal of Engineering Science Invention
ISSN (Online): 2319 – 6734, ISSN (Print): 2319 – 6726
www.ijesi.org Volume 2 Issue 10ǁ November 2013 ǁ PP.35-42
Performance Evaluation of Irrigation System an Overview
S.C.Deshmukh.
Bvdu,Coe Pune
ABSTRACT.: Management reforms are considered one of the best alternatives in increasing efficiency Of the
irrigation systems. Transfer of day-to-day operation and maintenance to farmers is not a new concept. However
due to lags, even now it is a hot issue in developing countries. In this context of growing argument about the
transfer of management of public irrigation systems to the Water Users’ Group, this paper examines the
comparative performance of farmer-managed and agency-managed irrigation systems. In this paper “irrigation
water management “is considered as one of the activities of the irrigation scheme. Three phases of irrigation
water management namely planning, operation and evaluation are identified. A framework for the performance
assessment of irrigation water management in heterogeneous irrigation schemes is proposed in this paper,
based on earlier studies made in this direction. The paper presents three types of allocate measures
(productivity, equity and reliability) and five types of scheduling measures (adequacy, flexibility, sustainability,
social impact and efficiency), together with the methodologies for estimating these for the scheme as a whole
during different phases of irrigation water management.This paper recommends a specific set of indicators for
measuring performance. Although the primary focus is on the management of canal systems for agricultural
production, the paper also discusses indicators that can be used for assessing longer term performance,
including physical, economic and social sustainability. Finally, the paper highlights the crucial importance of
strategic, as well as
operational management performance..
KEY WORDS: adequacy, equity, irrigation water management, performance assessment, productivity,
Reliability, sustainability, social impact.
I.
INTRODUCTION
Developing countries have made huge investments in infrastructure for irrigation in the form of
irrigation schemes over the last half century, realizing its importance for food production for the growing
population. This investment, together with improved crop production technologies such as use of fertilizers,
hybrid varieties, plant protection techniques, etc. has enabled many countries to move towards achieving selfsufficiency in food production. Nevertheless there is also a perception that many irrigation schemes do not
perform up to expectations or achieve the goals. Therefore the issue of equity was not addressed.A set of
comparative performance indicators is defined, which relates outputs from irrigated agriculture to the major
inputs of water, land, and finance. five indicators are presented with the objective of providing a means of
comparing performance across irrigation systems. These indicators require a limited amount of data that are
generally available and readily analyzed with respect to farmers participation. Results of application of the
indicators at irrigation systems are presented and large differences in performance among systems are shown. In
spite of uncertainties in estimation of indicators, the large differences discerned by the indicators justify the
approach taken.Previous studies that used the multi field type of model Sritharan et al. 1988 and Shyam et al.
1994_ produced the allocation plans and water delivery schedules for each allocation unit or field for optimum
productivity.
These studies discussed or estimated the performance measure of equity for the optimum allocation
plan, as they obtained the distribution of the resources by allocation unit. Therefore the methodologies included
in these models fall in the second category of methodologies, which optimizeproductivity while addressing the
issue of equity. However these models did not aim for optimization or maximization of the equity. The models
which are of simulation in nature such as reported by Keller _1987_, Jian _1990_, and Steiner and Walter
_1992_ estimated the equity for the given land and water resources allocation plan or for specified crop areas
and the water distribution rule. But these models did not attempt to optimize productivity or equity.
II.
IRRIGATION AND PERFORMANCE
Performance assessment has been an integral part of irrigation since man first started harnessing water
to improve crop production. The consequences of failing to monitor performance have also been known for
many centuries: The twentieth century has seen a massive growth in irrigation. About 35% of all food grown is
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2. Performance Evaluation Of Irrigation…
produced on irrigated land, and is the primary factor enabling mankind to feed an ever increasing population.
Population increase in a finite world means that pressure to increase the productivity of both land and water is
intensifying, particularly as demands for non-agricultural uses of water continue to increase. Some 70% of all
water used in the world is for irrigated agriculture, but this figure will continue to decline as urban and industrial
demands grow. The pressure to produce more food with fewer resources requires that performance in terms of
both water and land utilization to improve.
To achieve this, irrigation managers, whether at national, system or farm level, will need to work
harder to meet the challenge of the future. In light of this scenario it is perhaps surprising that few irrigation
agencies include rewards for high performance as an incentive for staff to try to improve productivity: most
irrigation agencies have not adapted to the management Challenge following their establishment and growth as
design and construction agencies. At the same time, there are few clear and comprehensive guidelines available
to agencies or managers that can help them in the institutional and technical transformations that are
prerequisites for achieving high performance.
This paper is based on the belief that improvement in performance requires
three conditions that must be satisfied simultaneously:
 a framework for managers to use in assessing performance,
 a practical and useful set of indicators for measuring performance, and
 an appropriate incentive and reward system that will encourage managers to improve their current levels of
performance.
Performance of irrigation water management
Definition
Lenton (1986) described irrigation performance as knowing the extent to which an irrigation scheme
achieved established objectives. According to Abernethy (1989) the performance of an irrigation scheme is
represented by “its measured levels of achievement in terms of one, or several, parameters which are chosen as
indicators of the system’s goals.” While reviewing and proposing different methodologies for assessing
performance of irrigation and drainage schemes, Bos et al. (1994) commented, “performance assessment is,
despite its apparent simplicity, a very complex task” and cited the definition of performance proposed by
Murray-Rust & Snellen (1993) as “the degree to which an organization’s products and services respond to the
needs of their customers or users, and the efficiency with which the organization uses the resources at its
disposal”.
The performance of irrigation water management can be stated as “the extent to which the land and
water resources in the irrigation schemes planned for allocation to different users and their spatial and temporal
distribution in planning and operation stages follow the objectives of the irrigation scheme.
Evaluation of irrigation performance
Performance assessment requires a framework that enables a manager to effectively use the data
collected as part of the routine task of operating and maintaining irrigation systems. The purpose of any
framework is to form a link between repeated actions in such a way as to provide a learning experience for the
manager that allows things to be done better in each successive iteration. It has proven difficult for irrigation
managers to use frameworks developed for other large organizations.
In part this may be because, at least until recent years, performance criteria were not well defined for
monopolistic service organizations, and partly because of the unique and complex nature of irrigation. This
picture is now changing, and increased attention is being paid to frameworks suitable for assessment of
performance in irrigation. It is not the purpose of this paper to comprehensively review a wide range of
frameworks or to analyze them in detail. However, two approaches are described in this section that provide the
basis for developing workable frameworks.
There is considerable confusion over what is meant by an irrigation system, and what objectives are
being used by whom at different locations and different times. Small & Svendsen (1990) attempt to overcome
some of this confusion by describing irrigation as a set of nested systems, each of which has its own particular
set of objectives. The primary linkage between these systems is that the outputs from one system become part of
the inputs into the next system, establishing a means-end framework. They incorporate five systems into their
model:
 the irrigation system, which has as its function the conveyance of water from the source to the farmer's
field. The output from this system, water delivery at the farm gate, then becomes an input into
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
the irrigated agriculture system where farmers use water and other inputs to produce crops; these crops
become the inputs into
 the agricultural economic system that includes rain feed agriculture as well as
irrigation; the value of the crops produced then forms part of - the rural economic system that deals with the
entire set of economic activities in rural areas that in turn form part of the highest level,
Fig1: Nested System Network
The purpose of defining this nested set of systems is that it allows the actions of a manager at one level to be
placed in the context of the next higher level if irrigation delivery does not match the requirements of farmers
who are responding to irrigation as part of a wider set of agricultural tasks, then performance will suffer. It also
provides a clear way of splitting up objectives into constituent groups that reflect the purpose of that system: this
avoids the common pitfall of trying to meet too many different objectives simultaneously.
Three types of performance measures:
 process measures that refer to the processes internal to a system that lead to the ultimate outputs from that
system,
output measures that describe the quality and quantity of the outputs at the point where they become inputs
into the next higher system, and
impact measures that refer to the impact of these outputs on the wider environment.

The distinction is useful because it helps us to understand that performance means different
things to different people. Until the context in which a particular number or value is used has been defined,
the scope for confusion and misunderstanding will remain large.
Characteristics of performance measures
Abernethy (1989) pointed out that performance indicators should provide irrigation managers with the
answer to the following three questions.
1. “Does the quantity of water provided meet the growth needs of the crops planted in a given season?
2. How fair is the water distribution among multiple users of the delivery system?
3. Does the water delivery timing match the growth needs of the crop and expectation of the farmers?”
General features of performance indicators
Monitoring is essential in providing the basic data used for performance assessment, but in its raw form
it is merely data. A true performance indicator includes both an actual value and a target value that enables the
user to quickly assess the amount of deviation and a standard that allows the manager to determine if the
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deviation is acceptable. It is therefore desirable wherever possible to express indicators in the form of a ratio. It
is important to ensure that the indicators selected for a system will describe performance in respect of the
objectives established for that system. It is this process that links the use of indicators to the overall performance
assessment framework. A good indicator can be used in two distinct ways.
It tells a manager what current performance is in the system, and, in conjunction with other indicators,
may help him to identify the correct course of action to improve performance within that system: in this sense
the use of the same indicator over time is important because it assists in identifying trends that may need to be
reversed before the remedial measures become too expensive or too complex.From the perspective of
operational performance, performance indicators are comparatively easy to define. They will normally be simple
ratios of actual to target conditions, and the result of the performance assessment process will be to either
change operational inputs so as to better achieve the target.
Classification of indicators
Performance indicators are grouped as,
a. Water supply performance. This deals with the primary task of irrigation managers in the capture, allocation
and conveyance of water from source to field by management of irrigation facilities. Indicators address several
aspects of this task: efficiency of conveying water from one location to another, the extent to which agencies
maintain irrigation infrastructure to keep the system running efficiently, and the service aspects of water
delivery which include such concepts as predictability and equity.
b. Agricultural performance. This addresses the direct impact of operational inputs in terms of such aspects as
area actually irrigated and crop production, over which an irrigation manager may have some but not full
responsibility.
c. Economic, social and environmental performance. This deals with the impact of both operational and
agricultural inputs on the viability and sustainability of irrigated agriculture; these impacts include both physical
and socio-economic sustainability of irrigated agriculture. It goes from the specific aspects of irrigation
management where system-level managers have direct control over water delivery, to less direct outcomes such
as agricultural production, then on to the less tangible and more subjective aspects of individual performance
and the performance of agencies. Using performance indicators in a spatial dimension also enables managers to
identify precise locations at which problems are arising, and where to take remedial action. Dividing the system
into several sub-systems, and assessing the performance at these lower levels, helps describe system
performance more effectively. A system experiencing water distribution problems, for example, would need to
know whether the most urgent management inputs are required at main, secondary or tertiary level.
Water supply performance
Water supply performance parameters are concerned with assessment of the water supply function of
the conveyance system: they cover the volumetric component that is primarily concerned with matching
supplies to crop demand, as well as the rather more subjective concept of reliability that may affect the users'
capacity to manage water efficiently, and the socially oriented aspects of equity. These three aspects all
represent facets of the concept of service being provided to water users. We focus our attention on this 'core
business' of the organization managing the 'main system', the diversion, conveyance, and distribution of water to
the users, i.e., to the point where it is handed over to an organization intermediate between individual farmers
and the main system management, or in the absence of such an organization, to individual farmers.
Conveyance indicators
The primary task of organizations managing irrigation systems is to deliver water in accordance with a
plan. Indicators in this section are therefore those that guide managers in respect to water delivery performance.
In most respects they will be short term in nature, referring to performance in the space of a day or similar time
frame. The simplest, and most short term, performance indicators are those that compare actual discharge to an
intended or target discharge at any given location in the system. It is convenient to differentiate between
instantaneous measures and those that cumulate performance over a specified period of time. The simplest and
yet probably the most important hydraulic performance indicator is:
Delivery Performance Ratio =
Actual Discharge
Target Discharge
This measure enables a manager to determine the extent to which water is delivered
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as planned at any moment in time and at any location in the system. The primary utility of Delivery
Performance Ratio is that it allows for instantaneous checking of whether discharges at any location in the
system are more or less as intended. It is obvious that the more frequent the measurement
the greater the likelihood that managers can match actual to target discharges.
Water Delivery Performance =
Actual Volume.
Target Volume
Over a sufficiently long time frame (e.g., monthly, or over three or four rotational time periods) it can
be assumed that if total volume delivered is close to intended, then the management inputs must be effective.
Efficiency- A related set of indicators refers to efficiencies. In most cases, efficiencies deal with volume
delivered within a set time period rather than instantaneous discharge. Efficiency is a measure of hydraulic
conditions in a spatial context over a specific time period.
Maintenance indicators
In contrast to the considerable work done on water delivery performance indicators, remarkably little
attention has been paid to assessment of performance in respect of maintenance of irrigation infrastructure. This
is despite the fact that physical infrastructure is the most costly item in irrigation development and in the
subsequent rehabilitation of older systems. Maintenance is designed to accomplish three main purposes: keeping
canals in sufficiently good condition to minimize losses and sustain designed discharge-head relationships,
safety, and keeping water control infrastructure in working condition.
Conveyance efficiencies provide the best way of assessing whether canal maintenance is required. By
tracking changes in conveyance efficiencies over time it should be possible to establish criteria that will indicate
when canal cleaning or reshaping is necessary. In many systems this is undertaken subjectively on appearance
rather than using a more analytical approach. An alternative measure of maintenance performance is to assess
the extent to which control structures can be operated as intended.
Allocative type performance measures
The allocative type performance measures are those which need to be attended primarily during the
allocation of the resources at the planning stage. Allocation of the resources influences production, area to be
irrigated, net return, distribution of the resources to the users based on certain considerations, or combinations of
these. Hence we classify the performance measures as,
1. Productivity
2. Equity
3. Reliability
Scheduling type performance measures
The irrigation schedule (consisting of the temporal or intra seasonal distribution of the resources to
different users) needs to be prepared for the allocation plans developed according to the objectives of the
scheme. Depending on these objectives, the schedule should be such that water deliveries may need to be
adequate both in planning and operation, reliable when in operation considering all the complexities in the
irrigation scheme, flexible and sustainable.
Depending on the objectives of the scheme we propose following five scheduling type performance measures.
1. Adequacy
2. Flexibility
3. Efficiency
4. Social Impact
5. Sustainability
Features of the Selected Indicators
Minimum set of external indicators was originally presented by Perry (1996). The indicators have been
widely field-tested and slightly amended, resulting in this present list. The intent of presenting this set of
indicators is to allow for cross-system performance. Some of the features of the indicators are:
• The indicators are based on a relative comparison of absolute values, rather than being referenced to standards
or targets.
• The indicators relate to phenomena that are common to irrigation and irrigated agricultural systems.
• The set of indicators is small, yet reveals sufficient information about the output of the system.
• Data collection procedures are not too complicated or expensive.
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• The indicators relate to outputs and are bulk measures of irrigation and irrigated agricultural systems, and thus
provide limited information about internal processes.
This set of indicators is designed to show gross relationships and trends and should be useful in
indicating where more detailed study should take place, for example where a project has done extremely well, or
where dramatic changes have taken place. This approach differs from that of using ratios of actual to target in
that the interpretation of these ratios relative to performance is not always clear (e.g., if the target value is 1, is
0.9 better than 1.1?) . A relative comparison of values at least allows us to examine how well one system is
performing in relation to others. And, if we have enough samples, this approach may ultimately allow us to
develop standards and targets.
The main audience for these external indicators comprises policy makers and managers making longterm and strategic decisions, and researchers who are searching for relative differences between irrigation
systems while the main audience for internal indicators comprises irrigation system managers interested in dayto-day operations.
Productivity
The productivity is related to output from the system in response to the input added to the system and
there are several indicators of productivity. The principle output of the scheme is the crop produce or its
economic equivalence and the area irrigated. These need to be assessed seasonally or annually. The productivity
can be indicated by measuring these outputs in gross terms or relative to input utilized.
Equity
Water is a scarce resource in many tropical countries and some may argue that it is advisable to achieve
the maximum productivity in its use. However in these countries, the objective of social justice in the irrigation
scheme may also be important and many people’s livelihoods may depend on their irrigation supplies. Thus the
allocation of water to achieve the maximum productivity is not the only objective but to allocate those resources
such as water and area equitably according to the prevailing equity objectives is necessary to ensure social
justice.
Reliability
Water allocation or supply may be less than maximum demand (estimated with potential crop water
requirement). However, in operation it is necessary to match the water deliveries to allocations, which may be
less than maximum demand, as in case of deficit irrigation. If water is delivered to the farmers in accordance
with the schedules prepared during the planning process, the supply is considered to be reliable; otherwise the
supply is unreliable. The reasons attributed to the unreliable supply are many: water availability in the irrigation
scheme is lower than estimated during the allocation process, unexpected demands arise from sectors other than
irrigation, inappropriate consideration of the capacity of the water distribution system, canal breakage and theft
and management capacity or capability of the irrigation organization to deliver the scheduled supply.
Scheduling type performance measures
The irrigation schedule (consisting of the temporal or intra seasonal distribution of the resources to
different users) needs to be prepared for the allocation plans developed according to the objectives of the
scheme. Depending on these objectives, the schedule should be such that water deliveries may need to be
adequate both in planning and operation, reliable when in operation considering all the complexities in the
irrigation scheme, flexible and sustainable. Depending on the objectives of the scheme we propose following
five scheduling type performance measures.
1. Adequacy
2. Flexibility
3. Efficiency
4. Sustainability
5. Social Impact
Adequacy
Adequacy deals with water supply to the crop relative to its demand. The measure of adequacy, relative
water supply (RWS), proposed by Levine (1982) is the most comprehensive. RWS is the ratio of supply due to
irrigation and effective rainfall to the demand due to evapotranspiration and other needs.This indicator in itself
or in little modified form (to account for variation in supply and demand) was used or proposed by many
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(Keller, 1986; Moya &Walter, 1988; Oad & Padmore, 1988;Weller, 1991; Sakthivadivel et al., 1993;Bos et al.,
1994).
Flexibility
The water delivery schedules decided during planning are often subjected to changes. These changes
are firstly due to variability in weather parameters, which cause the deviation of supply and demand during
actual operation from those considered during planning. Secondly, there are different types of interventions
when the scheme is in operation. The irrigation authorities are interested to know the influence on the outputs of
any change in water delivery schedules during the operation. These outputs are in the form of allocative types of
performance measures, i.e.
productivity and equity and scheduling type of performance measure, i.e. adequacy. Once the areas are
allocated to different crops for irrigation and the operation of the scheme has begun, any changes in the water
delivery schedules should cause minimum reduction in the output or tend to recover towards the intended
output. In short it is necessary to know how flexible are these schedules to take in these changes. We define
flexibility as “the ability of the water delivery schedule of the allocation plan to recover from any changes
caused in the schedule.” This needs consideration during planning of the irrigation water management. The
schedules based on a management strategy of full or over irrigation are normally more flexible than those based
on deficit irrigation. Achieving high flexibility in water delivery schedules may require compromising on other
performance.
Sustainability
Sustainability is the performance measure related to upgrading, maintaining, and degrading the
environment in the irrigation scheme. According to Abernethy (1986), the sustainability is the most difficult
factor to encompass and refers to the issue of leaching, drainage and Stalinization which if not attended to
properly, may shorten the system’s life. Though a lot of work has been published on the indicators of
performance measures such as productivity, equity, adequacy, etc. few efforts have been made to define the
indicators for sustainability. The indicators should enable the irrigation authorities to know which management
strategy or option is more sustainable or environmentally friendly and how the chosen management strategy
performed for sustainability while the scheme was in operation.
Efficiency
Allocation plans are developed using estimated efficiencies of water flow at various stages and time
and if these allocation plans are implemented properly, most of the performance measures described above will
be good indicators irrespective of whether the efficiency of the network is good or bad. However deteriorating
efficiency over the years will reduce the performance of the irrigation schemes over this period. Hence though
the efficiency is related to the maintenance of the physical infrastructure of the water distribution network it
needs to be evaluated as performance of the irrigation scheme when it is in actual operation.
This helps to show the causes of performance deviating from the desired standard. Efficiency is
important in two ways. Firstly, appropriate optimum allocation plans cannot be developed if proper
consideration is not given to efficiency. Inaccurate or simplified estimates also have a major influence on other
performance parameters such as productivity, adequacy, equity and reliability.Secondly, the inspection of
efficiencies over space and time at different levels enables the irrigation authorities to learn which part of the
scheme is inefficient, where it is inefficient and how it is deteriorating. It is necessary to define and use
efficiencies at different levels in the scheme, as the measures to improve these efficiencies are different at these
levels.
Social Impact
Social impact refers to the effects of irrigation on people. Measurements can include comparisons of
irrigated and adjacent non-irrigated areas, variation over time and space within the irrigated area, and variations
among socio-economic classes on specific social parameters. In multipurpose projects measures of the benefits
of non irrigation uses of water, such as recreation or fishing, could also be incorporated. Managers and policy
makers need to decide on the priority issues, and develop their own indicators for these. The most effective way
of obtaining the data required to measure social impacts is through sample surveys. If an agency is able to
contract periodically with a local research group to carry out such 'market research' it could be very useful. For
the purpose of this paper, however, we assume that the irrigation agency will use data to which it has direct
access, whether collected by its own staff or other agencies. Sometimes this indicator can be used as an indirect
measure of farmer satisfaction: the higher the ratio, the more the satisfaction. Other feasible approaches to
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8. Performance Evaluation Of Irrigation…
measuring farmer satisfaction include carefully recording the number, types, and temporal and spatial variation
in farmers' complaints received either in writing, or through intermediaries, or through meetings with farmers. In
many countries, there are departments of agriculture, labor, or census which collect basic agricultural and
economic data. These can be used very easily by irrigation managers as sources of information on socioeconomic impacts and trends, such as employment, wages and poverty levels.
III.
CONCLUSION
Irrigation water management in irrigation schemes is complex due to their heterogeneity. Three phases
of irrigation water management namely planning, operation and evaluation were identified. Previous studies on
the performance assessment of irrigation scheme have provided the conceptual framework for performance
measurement. This has been extended in this paper for the qualitative and quantitative evaluation of
performance during every phase of irrigation water management.
Two types of performance measures were proposed in this paper: the allocative type comprising
productivity and equity; and the scheduling type comprising adequacy (excess), reliability, flexibility,
sustainability and efficiency. These performance measures are described with different attributes in this paper.
The methodologies to estimate these measures explained in this paper provide the irrigation authorities with the
information on the performance of irrigation water management in the scheme, their management capability, the
response of the irrigation water management to variations in climatological, physical and management aspects
and insight to improve the performance during different phases of irrigation water management.
Although the primary focus is on the management of canal systems for agricultural production, we
have also discussed indicators that can be used for assessing longer term performance, including physical,
economic and social sustainability. Finally, the paper has highlighted the crucial importance of strategic as well
as operational management performance. It is unlikely that in any single evaluation there will be sufficient time
or resources to assess all aspects of performance simultaneously.
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