Irrigation Investment Research Articles

Sustainability issues and technology choice in irrigation investment

This paper discusses the concept of sustainability and its relevance in assessing technology choice issues in irrigation investment appraisal. Although, sustainable agricultural development is a desirable goal, the concept cannot lead to practical project appraisal recommendations unless it is properly defined and it is introduced in the project evaluation process as a set of selection rules. This paper discusses the concepts of sustainable development and project sustainability, and continues with rules that can be used in the project selection process to examine: (a) ecological; (b) operational; and (c) financial sustainability of projects. The paper concludes that sustainability is a useful concept to use in analysing alternative options for technical, organizational and economic issues in irrigation project appraisal.

Large Scale Irrigation in Northern Nigeria: Performance and Ideology

Large-scale irrigation (LSI) has been an important feature of agricultural development investment in sub-Saharan Africa, yet LSI projects have a poor performance record. Enthusiasm for an investment in LSI was particularly strong in northern Nigeria in the 1970s and 1980s and a number of areas were developed for irrigated smallholder production by Federal River Basin Development Authorities in Sokoto, Kano and Bomo States. However, there have been significant problems of escalating capital costs, delayed construction, low yields, erratic water supply and poor management, and adverse environmental and socio-economic impacts in floodplain environments. Experience with these problems in northern Nigeria is reviewed, and the persistence of LSI in Nigeria in spite of its poor performance is discussed in the context of political economy and the ideology of irrigation. This ideology, of irrigation as a modernizing 'technofix' solution to perceived development problems of environment and economy, served to legitimize continued investment in large-scale irrigation. Confidence in irrigation's potential contribution to Nigerian development still persists but the focus of attention has shifted to small-scale irrigation. Some implications of this new enthusiasm are discussed.

A dynamic optimization model for irrigation investment and management under limited drainage conditions

Irrigation management in a field underlain by a water table aquifer is considered. The water table varies with deep percolation which is in turn a function of the irrigation system and applied water quantities. A drainage system is installed once the water table reaches a maximum height. Optimal irrigation systems and applied water quantities are calculated using dynamic programming. For low confining layer conductivities, deep percolation is progressively reduced through time under optimal management by a combination of improved irrigation systems and reduced water applications. This delays the water table build‐up and postpones drainage costs. Optimal management for a moderately conductive confining layer results in a cyclical policy in which periods of improved irrigation systems and reduced water applications are alternated with periods of traditional irrigation systems and water applications to maintain the water table below the depth requiring drainage system installation.

Adopting water-conserving irrigation technology: The case of surge irrigation in Arizona

Surge-flow irrigation technology is a potential means for increasing irrigation efficiencies in desert agriculture. An economic analysis of the adoption decision for Arizona farmers reveals that an investment in surge irrigation is only economically viable when developing new agricultural lands or where gated pipe is already in use. Since the majority of the agricultural land in Arizona is furrow irrigated using ditches and syphon tubes, the potential for high adoption rates on existing farmland is rather limited. The analysis indicates that water costs, under conservative but realistic assumptions, would have to rise to US$ 0.08/m 3 (US$ 100 per acre foot) before surge irrigation would be economically viable as a substitute for open ditch furrow irrigation. Further research is needed on potential labor savings and management efficiencies related to surge irrigation in order to measure potential profitability more accurately.

Progress and Problems of Irrigation Investment in South and Southeast Asia

ABSTRACT Irrigated area in the world has increased from 40 million ha in 1900 to more than 225 million ha. Irrigation investment has accounted fro 28 percent of all World Bnk funding during the past decade. However, since 1980 there has been a distinct diminishing in the rate of irrigation development. Irrigation investments have not proven to be as productive as originally expected. In fact, problems of funding for O & M and overall irrigation managent have become so acute that major donors are starting to seriously question the wisdom of additional irrigation investment. How well third world countries are able to develop and implement programs to increase funding for O & M and improve the quality of management will determine the level of future investment in irrigation

Irrigation in Drought Prone Areas

Investment in irrigation forms a major part of the strategy of increased agricultural production and rural development in the successive five year plans. This calls for greater efforts on preparation of basinwise regional plans for optimum development of water and related resources, within the national policy framework. There is a greater need for laying stress on economic efficiency in planning, implementation and management of irrigation projects so that the projected benefits to the farmers are achieved. Irrigation planning and management pose problems which are extremely complex. It needs a comprehensive interdisciplinary approach drawing insights and skills from many fields to tackle these complex problems.

Estimating moisture availability for rice cultivation in Mwea, Kenya

Recent climatic events in Africa have shown the need for increased understanding of the vagaries of rainfall and the demands for water. Water availability and usage for agriculture must consider not only amounts but also the timing of water requirements during the growing season. Rice cultivation in Kenya is an important food source for which irrigation is essential to produce successful yields. In order to describe rainfall probabilities in relation to water demands, we have employed the Gamma Probability Density Function; for calculating crop water demands potential evapotranspiration calculations recommended by Doorenbos and Pruitt (1975) were used. Evapotranspiration and rainfall probabilities were calculated for twelve 10-day crop phenology periods during the rice growing season. A twenty-year sample was analysed for rainfall but data for only seven seasons were available for estimating evapotranspiration. Estimates obtained from fitting the 10-day periods for the twenty-year precipitation sample show that: (1) all individual crop periods are positively skewed (non-Gaussian); (2) periods of low amounts of precipitation are less skewed than for times of higher rainfall; (3) rainfall increases as the rice season progresses but the statistical variability becomes greater with the increased precipitation amounts; (4) there are no ten-day periods during the growing season in which rainfall probability equivalents are higher than 50% of the water demands; (5) during the initial stages of the growing season there is a substantial probability of receiving no rainfall at all; and (6) seasonal precipitation amounts as an indicator of the necessity to irrigate can be very misleading. The methodology used here is superior in irrigation investment decisions and estimations of maximum amounts of water needed in irrigation periods.

Technical change, employment, and supply response of agriculture in the Nile Delta: A system-wide approach

In this paper, a system-wide model of crop production in the Delta region is developed in order to comprehensively analyze Egyptian agricultural policies and also to identify the main causes of the slow growth of the sector in the seventies. Previous studies based on single-crop models have blamed the government's price policies as the culprit. Our estimation results show that although there might have been some gains from appropriate changes in the relative prices of crops, price policies in general were not responsible for the poor performance of the sector, since the aggregate supply response of crops to the price levels in indeed quite low. The main factor which seems to explain the slow growth of agriculture is the decline in the level of investment in irrigation and drainage. Investment in land reclamation, on the other hand, has had negative effects on the short-run growth of the sector. On the question of the impact of increased mechanization on Egyptian agriculture, we find that mechanical power has essentially displaced animals in crop production without much affecting the growth rate of the sector or its employment opportunities directly.

Reduced Pressure Irrigation Investment Economics

Because reduced pressure irrigation is energy saving, many commentators conclude that it is also cost saving. The validity of this proposition is examined in this article. A central focus is whether yields are likely to be less with reduced pressure. If yields are not likely to be less and the purchase of a new irrigation system is expected to be profitable, clearly, a reduced pressure unit should be selected. If a yield reduction is not in prospect and the conversion of an existing conventional high pressure system to reduced pressure is contemplated, the decision revolves around the present value of the prospective annual energy cost savings from reduced pressure (the break‐even investment) relative to a dealer's cost for making the conversion. The article also shows that even small reductions in yield from reduced pressure irrigation (e.g., less than 5%) can completely erode the economics of investing in reduced pressure units.

Monitoring and Evaluation of Benefits in Agriculture and Rural Development

In the last two decades, developing countries in the Asian and Pacific region have made large investments in agricultural, irrigation and rural development projects. Many of the projects have been assisted by bilateral and multilateral development agencies. While the rapid progress in agricultural and rural development in the region since the mid-1960s can be directly associated with these investments, the performance of many projects has fallen short of expectations. This situation has led to increasing attention being given to the design and implementation of projects. As a result, new initiatives have been taken to improve the performance of projects. These range from efforts to increase the participation of beneficiaries in the designing and operations of projects to improvements in project management procedures and skills. This article focuses on one initiative that has implications for almost all efforts to improve the efficiency of these investments, namely, monitoring and evaluation of the benefits of development projects…

Optimal Irrigation Pivot Location on Irregularly Shaped Fields

AbstractAlthough annual rainfall in the Southeast is adequate, its distribution is a potential constraint to agricultural production. Farmers require production information concerning efficient use of irrigation technology adapted to regional growing conditions. Selection of optimal position, size, and number of pivots in center pivot irrigation systems poses special problems on small, irregularly shaped fields. In the southeastern United States, field size and shape are often varied and irregular. A mixed integer programming model was constructed to assist in irrigation investment decisions. The model is illustrated using irrigated peanut production in southeast Alabama. Results indicate the importance of economic engineering considerations.

A Bioeconomic Simulation Analysis of Irrigation Investments

Agriculture is unique with respect to the importance of weather variability on output and profits. Irrigation has long been recognized as a means of increasing yields and profits in the arid west, and recently interest in investments in supplemental irrigation in humid areas has accelerated (Brown and Skinner; Hewitt et al.; Levins; Clouser et al., Worm et al.; Schoney and Massie).

Extensive versus Intensive Agricultural Development: Induced Public Investment in Southeast Asia, 1900–1940

Kikuchi and Hayami found that irrigation investments were undertaken in East and Southeast Asia when the costs of increasing output through irrigating were lower than through bringing more land under cultivation. In Thailand, however, despite the lower costs of irrigation, the investments were postponed for several decades. The delay was due to a divergence between national security and economic development goals and to a conflict of private versus public interests. The results highlight the importance of the returns to decision makers in determining the amount and timing of public investments.

Returns to Public Irrigation Development

Recently, returns to public investment, in general, and irrigation investment, in particular, have received critical attention from economists (Young, Martin). Two of the important, interrelated issues are (a) how to measure beneficial impacts of irrigation projects and (b) who should pay for this public investment. Once we know the magnitude of benefits created and the beneficiaries, we should be able to recommend who should pay for this investment and how much they should pay. For simplicity, we classify the beneficiaries of public irrigation into two major groups, producers and consumers. Most studies (Freeman, Keleta, U.S. Water Resources Council, U.S. Department of the Interior, and references cited in Young, Young and Gray, and Martin) on returns to irrigation emphasize production gains from irrigation. The gains enjoyed by consumers are typically omitted, the exception being Martin's work. The implicit assumption here is that the relevant commodity demand curves are perfectly elastic. As Martin argues, this assumption may be valid for a particular project, but not for the general equilibrium context taking into account all the projects undertaken in a period. Thus, the proper demand curve to use is not perfectly elastic, but downward sloping. For a valid evaluation of benefits of public irrigation, one should account for both consumer and producer surpluses. Doing that will provide us with objective criteria concerning who should pay how much for irrigation investment. Thus, the specific objectives here are (a) to derive analytical expressions for measuring consumer and producer surpluses when public irrigation investment shifts the supply function for commodities; and (b) to derive expressions for the exact distribution of gains between consumers and producers. I Consumers' and Producers' Surpluses with Irrigation

Increasing Food Production in Asia Through Investments in Irrigation: Potential and Problems

Technological developments in rice production in Asia have greatly increased the potential returns to irrigation investments. It is likely that a substantial amount of resources will be allocated to irrigation development in the next two decades. But past experience suggests that the returns actually realized on these investments will be disappointing unless greater attention is paid to problems of effective water management, particularly in the main irrigation system. Human and institutional capabilities, and not physical or financial capital, are likely to be the most limiting factors in dealing with these problems.

Economics of irrigating grassland in the United Kingdom

AbstractA mathematical model which simulates the response of grass to irrigation over a range of rainfall and soil conditions is described. Using the model the probable costs and benefits from investing in irrigation facilities for intensive beef and dairy production have been determined. Irrigation only appears to show a reasonable return on investment where the mean summer rainfall is less than 350 mm or the water‐retaining capacity of the soil is low. Furthermore, investment in irrigation is only likely to be logical where the rate of fertilizer N applied is greater than 300 kg N ha‐1. It also appears that a strategy of partial irrigation is unlikely to yield the maximum financial gain. Overall the indications are that for the foreseeable future only a small percentage of the total grassland area in the UK can be irrigated profitably.

A case for professionalization of water management in irrigation projects in India

AbstractThe heavy investment in irrigation in India has not brought the expected benefits and this article argues first that a major difficulty arises from the way irrigated water is administered. The distribution of water is controlled by irrigation engineers who lack the knowledge and information to manage water in a way that maximizes agricultural production and achieves the confidence of farmers. The staffing structure and related professional values discourage the development of a new more appropriate specialism. The article goes on to argue that a new organization of work and associated staffing structure is needed which will encourage a new professional specialization bringing together staff and expertise currently dispersed in separate specialisms in engineering, agronomy and other aspects of agriculture.

Input and output constraints affecting irrigation development

In many of the developing countries the expansion of irrigated agriculture is used as a major development tool for bringing about increases in agricultural output, rural economic growth and income distribution. Apart from constraints imposed by water availability, the major limitations considered to any acceleration of such programs are usually thought to be those of costs and financial resources. However, as is shown on the basis of empirical data drawn from Mexico, in reality the feasibility and effectiveness of such development programs is even more constrained by the lack of specialized physical and human factors on the input and market limitations on the output side. On the input side, the limited availability of complementary factors such as, for example, truly functioning credit systems for small-scale farmers or effective agricultural extension services impose long-term constraints on development. On the output side the limited availability, high risk, and relatively slow growth of markets for high-value crops sharply reduce the usually hoped-for and projected profitable crop mix that would warrant the frequently high costs of irrigation investments. Three conclusions are drawn: 1. (1) Factors in limited supply have to be shadow-priced to reflect their high opportunity costs in alternative uses. 2. (2) Re-allocation of financial resources from immediate construction of projects to longer-term increase in the supply of scarce, highly-trained manpower resources are necessary in order to optimize development over time. 3. (3) Inclusion of high-value, high-income producing crops in the benefit-cost analysis of new projects is inappropriate if these crops could potentially be grown in already existing projects.

ACCOUNTING AND REPAYMENT PROVISIONS OF THE PICK‐SLOAN MISSOURI BASIN PROGRAM1

ABSTRACT: The accounting and repayment practices employed by the Water and Power Resources Service (WPRS) greatly distort the actual resource allocation process and the ultimate repayment to the Federal Treasury. Through a series of transfers of capital repayment obligations to future development with modest or no interest charges, the repayment is reduced to only a fraction of the amount implied. In the case of the Pick‐Sloan Missouri Basin Program, the public subsidy of hydroelectric power is estimated to be $2 for every $1 of repayment. For irrigation investment, the direct repayment to the Federal Treasury is less than 10 percent of the annualized cost of the public investment, with irrigators repaying at a rate of less than $0.03 for every dollar of public expenditure.

Monitoring Land and Water Use in the Gefara Region by Satellite Imagery

Over ninety-seven per cent of Libya's water for agricultural and other uses came from groundwater in 1980 (Pallas). By then it was obvious that the renewable water in the coastal aquifers was seriously depleted and would not be sufficient to sustain the levels of water use implied by the national agricultural development plans. Meanwhile the potential of the southern aquifers had become apparent through their development in Kufrah, Sarir and Fezzan.The Gefara Plain has always been the major agricultural area of the country and until 1973, both before and after independence, had always attracted the bulk of public and private investment in irrigation. The decline in the level of the coastal groundwater was observed, or predicted, by all hydro-geologists who looked at the Gefara Plain after 1950, although it should be remarked that the observations were made on the basis of imprecise and unrepresentative data. Even by 1980 figures on groundwater recharge (estimated from landuse and assumed pumping levels) were numerous and inconsistent making it difficult for policy makers to determine the economies required and the measures necessary to achieve the optimum management of water resources. Depending upon which estimates of recharge and withdrawal were used, the amount by which withdrawal exceeded recharge varied from three to eight times.In these circumstances it was obviously prudent to attempt to determine the water balance from the Gefara Plain, and to this end a study was commissioned by FAO, on behalf of the Secretariat of Agriculture in Tripoli, for a study of recent satellite imagery to determine whether this inexpensive system of resources survey could make a contribution to planning water use in north-west Libya. By providing data on the irrigated area. From such data the water use element of the water balance equation could be estimated.