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ANNEXES


Annex 1: Planning a large irrigation project in the period 1950-70

This annex draws heavily on a paper prepared by two engineers from the Bureau of Reclamation published in the 1955 U.S. Yearbook of Agriculture. This paper presents the approach to planning of large irrigation projects in the 1950s. The Bureau of Reclamation has considerably influenced the planning process adopted by lending agencies. The focus was on the classical engineering studies, land classification and the capacity of the farmers to pay.

A large-scale irrigation development is a substantial undertaking that requires investigation, planning and progress in accordance with a defined course of action. It is interwoven with economic, social, legal, political and interregional and international problems.

The reconnaissance stage, the first stage of planning, involves a short review of all major engineering, land and water problems to determine whether a more detailed investigation is warranted. Planning during the feasibility stage, the second stage, should be detailed and conclusive in the formulation of plans for the irrigation project, recognizing that the plan proposed now may be subject to change when the irrigation project is being constructed.

Studies have to be made of groundwater possibilities since large projects often combine the use of surface and groundwater to provide the full requirements. Quality of water must be determined. Flood flows require special consideration: structures must be designed with adequate spillways to accommodate these floods.

The feasibility of an irrigation project depends on continued productive ability of the lands. Detailed description of land classification studies is provided. If the water supply is the limiting factor, the arable land classification data and the underlying surveys are used as the basis for selecting the locations of the irrigable lands to be included in the project.

The application of engineering skills and judgment is essential to the design and construction of works to deliver irrigation water to the land in controlled and adequate amounts for crop use. In that, the important steps are engineering surveys and explorations, including geological interpretations, preparation of preliminary designs and cost estimates, and the determination of annual operation, maintenance and replacement costs.

During the preparation of feasibility designs, studies are made to deter-mine the structures best suited to the conditions encountered. Engineering economics is important: the engineer must design a structure for the job - the most economical in first cost and in annual cost of operation, maintenance and replacement.

To make a reasonable estimate of the annual operation, maintenance and replacement cost, the project plan must be crystallized, extensive operation on each important structure must be available and the farm layout must be determined. With such data available, an organization necessary for the operation and maintenance can be planned, equipment requirements estimated, materials and supplies needed for operation and maintenance determined and the probable life of structures calculated.

Repayment studies are made to determine payment capacity of the water users and to make recommendations for repayment of construction costs allocated to irrigation. Determination of payment capacity is accomplished by an extensive study of the agricultural expectancies of the project area without the proposed development in comparison with conditions assumed to exist under the proposed development. The main tool of the study is the farm budget analysis.

Project development may be further justified by a comparison of the net benefits resulting from construction of the project with all anticipated costs of bringing about these benefits. The ratio of all net benefits to costs in excess of unity will indicate the desirability of the development.

Finally arrangements have to be made for financing if the project has been found feasible.

Sometimes the farmers are not familiar with the problems connected with irrigation farming, the need for the preparation of land to receive irrigation water, and the controlled application of water for best results. They may need help which can be made available through different agencies.

Annex 2: Abstracts from the FAO Guidelines for Planning Irrigation and Drainage Investment Projects

This annex reproduces the sections from the FAO Investment Centre Technical Paper No 11 which are dealing with water management and operation of irrigation and drainage systems.

Part I: Recent lessons and implications for planning

Choice of technology (page 29)

Commonsense dictates that the choice of a technology for irrigation should be based on its appropriateness for the cropping patterns intended and should also consider cost-effectiveness. In the past, irrigation engineers have tended to overlook an additional need: for the technology also to be matched to the level of sophistication of the operational capacity of the users. It has become increasingly obvious that the design process must start from a consideration of how the users will operate the system; this should be then designed to provide the optimum combination of efficiency in water use and cost-effective operation and maintenance. Equally important, the designer must consider how the users will cultivate their land and the implications that this may have for scheme layout. Thus it may be that the design which involves the lowest investment cost per hectare may not be the most cost-effective solution if it also involves a large number of staffers for its operation or if, because of operational difficulty, it cannot be used to capacity. On the other hand, a design of modern water control structures may not result in overall efficiency gains if the users reject the modern control in favour of their traditional proportional dividers.

The choice of technology, whether for new development or for the rehabilitation of existing schemas, has been the subject of much debate over the years. While most irrigation engineers would now agree that the starting point for design must be ease of operation, they still tend to polarize into two camps. One sees the problem largely as overcoming the hydraulic instability of extensively gated manually operated systems; it sees the solution as the modernization of these systems, adding automatic downstream control structures and other feedback mechanisms designed to achieve hydraulic stability. The other accepts the reality of farmers' damage in wet-season drought and so favours designs based on cruder and more robust structure; the possibility of just-on-time, demand-based delivery of water to crops is foregone, in the hope of preserving the civil works from interference.

Part II: The planning process

Activities for planning the preferred option (page 69)

Engineering studies should include: a) for schemes being considered for rehabilitation and upgrading, a detailed diagnostic operational study to identify the current condition of the infrastructure, constraints, sources of inefficiency and the scope for efficiency gains and b) preliminary engineering designs for the scheme layout, main structures and water supply focusing particularly on water saving measures and ease of farmer operation and management, including automatic controls if they are considered to be an appropriate technology.

Outline of a typical project document: project rationale and planning considerations (page 131)

The section on design considerations should address questions such as: the choice of technical strategy and technology to match operation and maintenance capacity (e.g. upstream versus downstream technology, automation, etc) and/or traditional water rights and methods of distribution, e.g. division structures that maintain traditional rights and farmers operational preferences.

Annex 3: Conventional terms of reference for consulting services for an Irrigation Improvement Project

The following are extracts from the terms of reference for a project approved by a donor agency in 1994. The terms of reference are limited to conventional engineering studies. They do not include a diagnosis of the performance of the existing projects, particularly in terms of service provided to users. The appraisal report for this particular project does not indicate the level of service to be provided under the project; it does not even include a short discussion on the water control strategy and equipment. Most recent appraisal reports of donors limit the discussion on operation and maintenance of the project to indicating the level of canals for which the agencies and the farmers are responsible.

Contracts for each subproject would cover the scope of work for engineering designs and construction supervision. Services to be provided for each subproject would include, but not be limited to, assistance in:

a) Collection and analysis of data

b) Preparation of work plans for all subproject components

c) Survey, investigation, design, layout, preparation of specifications, tender/construction drawings, consultants' cost estimate, and supervision of construction of the irrigation, surface/sub-surface drainage, and land levelling works

d) Establishment of criteria and procedures for technical work and construction specifications

e) Preparation of tender documents for civil works and required equipment

f) Quality control, including performance and/or ranging field and laboratory tests

g) Setting up monitoring systems for selected physical parameters and monitoring the physical and financial progress

h) On the job training and guidance of the implementing agency's assigned staff in materials inspection and construction technique

The main objective of the study for each subproject would be to provide recommendations on how best to organize water user groups along a convenient tertiary block service area perimeter, and to strengthen the functional capability of exiting water user groups.

Annex 4: Irrigation policy: Modernization of water resources in Brazil

This annex provides extracts from a policy note on irrigation modernization in Brazil, which is a good model of a new policy incorporating the principles developed in this document. Brazil is among the most advanced countries in Latin America in adopting modern irrigation technology. With some 65 percent of all irrigation under some form of aspersion, it is significantly ahead of most countries. In addition, technology use is highly diverse. Nearly all existing technologies are under use in some form or another. The paper recognizes that water user associations are only one type of private-sector participation. It also recommends the adoption of more efficient technologies to respond to the increasing demand for water for other sectors.

Irrigation has a crucial role to play in the transformation of agriculture and the improvement of economic and social conditions of the world population. Although the global demand for food is essentially met, hunger persists mainly because the hungry cannot translate their needs into demand or because civil disorder disrupts food flows.

Despite these expectations, irrigation expansion has slowed dramatically since the 1980s. Over the past decade, the worldwide trend has been towards emphasis on the rehabilitation and management improvement of existing schemes. The slowdown is probably linked to factors such as: a) the trend towards economic wide reforms that result in reduced fiscal resources for irrigation, a sector that has traditionally relied heavily on public funding; and b) growing adverse publicity related to negative environmental impact from both the development and abandonment of irrigation schemes.

There is a danger that countries will become complacent, reduce irrigation investment to unsustainable levels or abandon it altogether, and thereby trigger crises for the most vulnerable populations of society.

Irrigation is a case in point. Historically, except for a period of fairly significant investments and an effort to promote irrigation development in the 1960s and 1970s, the government of Brazil's attention to irrigation has taken a back seat to other uses, such as power and urban water supply. The situation persists even today as modernization reforms are focused mainly on the overall economy or, in the case of the water sector, more on overall water resource management, water supply and hydropower. As a result, changes needed to modernize the legal, institutional and policy framework for irrigation are lagging and irrigation development has been relatively stagnant for over a decade.

Need for irrigation reform

There is an abundant literature on the main issues affecting the irrigation sector in many countries, often described in the form of a vicious cycle caused by the lack of maintenance, poor irrigation service, farmer dissatisfaction, low rates of fee collection, weak irrigation budgets and, as a result, inadequate maintenance. In an attempt to break this cycle in the irrigation sector, governments and multilateral organizations have begun to promote new-style programmes that combine a mix of physical rehabilitation improvement and management reforms, improved financial performance and attention to operation and maintenance, stronger linkages to support services and overall water resources and user participation.

User participation, in particular, has drawn a lot of attention, in part because it enables public agencies to get out of a business where they have generally been inefficient. In this case the more conventional approach tends to focus on creating and building private water user associations or similar organizations that can take over irrigation management from public agencies. A less conventional view takes a more comprehensive approach, seeking to involve a variety of private-sector participants not only in irrigation management but also in financing and construction of such schemes, as well as multipurpose projects. In this case, water user associations represent only one type of private participation. Others include corporations (full-service irrigation companies, consulting firms, contracting firms), NGOs and the general public. This unconventional approach is particularly appealing because not only does it potentially minimize the inherent problems of public management but it also provides significant public-sector investment and cost savings. This is increasingly critical, as the growing investment needs of the irrigation sector are not likely to be met by public agencies constantly facing tight fiscal constraints.

Modernization vision

The need and types of irrigation reform seem to be well understood. However, a comprehensive vision of what the ideal, or modern, irrigation sector might look like is less certain. Part of the problem is that the irrigation sector tends to be highly complex, involving and/or affecting numerous other sectors and factors. Irrigation realities and policies vary substantially across countries.

There are at least seven elements that could be considered as fundamental for any modern irrigation sector. They are:

Regarding technology

Identifying what is modern (or most advanced) is perhaps straightforward. It is widely recognized, for example, that micro-irrigation uses water more efficiently, although it requires more investment and skilled labour than other types of irrigation technology and is sometimes less practical. It is clear that technological advancement is critical to sustain irrigation development over time. Again, in light of significant economic resources constraints, the cost savings and greater productivity that can be realized from adoption of such technologies is fundamental. Equally important, the population growth and rising income factors that may require increased food production from irrigated lands create conflicts among competing uses for water (i.e. hydropower, irrigation, water supply, environment, etc). As such, technologies that improve irrigation water use efficiency, thereby enabling a reduction in overall water use for irrigation, will be important in helping to minimize such conflicts.


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