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1.
This paper describes the practice of assetmanagement and its application toirrigation system maintenance. It thenpresents the application of a simplifiedasset management procedure for transferredirrigation systems in Albania. In thisapplication, the procedure was introducedto assess, monitor, and regulate, overtime, the condition of government-ownedirrigation infrastructure; management,operation and maintenance of which has beentransferred to Water Users Associations andFederations of Water Users Associations. The paper describes the procedures used tocarry out asset surveys, and to process anduse the data collected. The procedureshave been found to be relevant andapplicable to the conditions experienced inAlbania and a valuable mechanism forfocussing the attention of Water UserAssociations and Federations of Water UsersAssociations on sustaining and enhancingthe condition of the irrigationinfrastructure.  相似文献   

2.
This paper summarises the performance indicators currently used in the Research Program on Irrigation Performance (RPIP).Within this Program field data are measured and collected to quantify andtest about 40 multidisciplinary performance indicators. These indicatorscover water delivery, water use efficiency, maintenance, sustainability ofirrigation, environmental aspects, socio-economics and management. Theindicators now are sufficiently mature to be recommended for use inirrigation and drainage performance assessment.  相似文献   

3.
A crucial, yet little understood, element in the economic studies of irrigation is the role played by companies who manage the supply of water. Many of these companies are publicly managed as they have the potential to act as monopolists. Possibly as a consequence of their ownership structure, analysts have questioned the economic viability and management of these firms. The case is made that many of these companies do not run profitably, that they rely on government subsidies to survive, that they do not spend enough on maintenance and that they run down their capital base. The purpose in this paper is to specify the measures that allow analysts to examine the financial viability of a publicly owned irrigation management companies and to apply these to a scheme in Vietnam. Of concern and contention in any irrigation scheme is the price that a company should charge for water in order to recover costs in the short-run. It was found that the company under investigation could not operate without subsidies and did run down their assets. It was found that a great disparity exists between what the consumers were charged for water and what the company received for supplying it. To ensure the sustainability of the Irrigation Management Companies in long term, they may have to increase the water fee by 3.75 times the current rate set by the provincial government (US$ 20 per ha).  相似文献   

4.
The use of drainage systems for supplementary irrigation is widespread in The Netherlands. One of the operating policies is to raise the surface water level during the growing season in order to reduce drainage (water conservation) or to create subsurface irrigation. This type of operation is based on practical experience, which can be far from optimal.To obtain better founded operational water management rules a total soil water/surface water model was built. In a case study the effects of using the drainage system in a dual-purpose manner on the arable crop production were simulated with the model. Also, the operational rules for managing this type of dual-purpose drainage systems were derived.The average annual simulated increase in crop transpiration due to water conservation and water supply for subsurface irrigation are 6.0 and 5.4 mm.y–1, respectively. This is equivalent with 520 × 103 and 460 × 103 Dfl.y–1 for the pilot region (2 Dfl 1 US $). The corresponding investments and operational costs are 600 × 103 Dfl and 9 × 103 Dfl.y–1 for water conservation and 3200 × 103 Dfl and 128 × 103 Dfl.y–1 for subsurface irrigation. Hence, water conservation is economically very profitable, whereas subsurface irrigation is less attractive.Comparing the management according to the model with current practice in a water-board during 1983 and 1986 learned that benefits can increase with some 50 and 500 Dfl per ha per year, respectively.  相似文献   

5.
This paper presents a framework irrigation managers can use in assessing performance of irrigation, and recommends a specific set of indicators for measuring performance that the authors believe are practical, useful, and generally applicable. 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, and the necessity of having an incentive system that encourages managers to improve performance.  相似文献   

6.
This paper presents a framework for the use of asset management programs for short, medium and long-term financial planning and management of irrigation and drainage systems. Asset management plans provide decision-makers the information on costs of infrastructure and their management in different stages of the financial management cycle. Their use is clarified for defining service levels and their associated costs, allocation of cost to specific services, defining charges and service fees and preparing budgets and subsidy arrangements for operation, maintenance, rehabilitation or modernisation of infrastructure.  相似文献   

7.
水田灌排一体化系统的开发与应用   总被引:1,自引:0,他引:1  
分析国内外农业灌溉和排水领域发展的研究现状和目前常见的灌排装置的特点,针对中国灌溉排水研究领域对节水灌溉、控制排水设施的迫切需求,提出了水田灌排一体化系统的设计方案.该系统能根据农作物不同时期对水位的需求,充分利用灌溉和降雨的水量,较为精确地控制水田的灌溉和排水水位,解决了原有灌排设备无法同时实现灌溉和排水自动控制的难题.实际应用结果表明,水田灌排一体化系统试验区和对照区相比,降雨量增加利用150 mm,降雨利用率提高21%,减少灌水量21%;水稻亩产量增加4.3%;提高肥料的利用效率,减少农业面源污染.该系统结构简单、操作方便,具有可观的经济、生态效益和广阔的应用前景.  相似文献   

8.
Drainage water from the lower boundary of the root zone is an important factor in the irrigated agricultural lands for prediction of the water table behavior and understanding and modeling of water and chemical movement in the soil profile. The drainage coefficient is an important parameter for the design of subsurface drainage. On a 33,138 ha of the Nile Delta in Egypt, this study is conducted using 90 irrigation periods over a 3-year crop rotation to estimate the time-dependent drainage from the root zone and the design subsurface drainage coefficient with different cropping seasons and irrigation management levels.The results showed that the cropping seasons and the irrigation management levels as indicated by different irrigation efficiency are significantly affected the drainage rate from the root zone and the design value of subsurface drainage coefficient. Drainage rates from the root zone of 1.72 mm/d and 0.82 mm/d were estimated for summer and winter seasons, respectively. These rates significantly decreased in a range of 46% to 92% during summer season and 60% to 98% during winter season when the irrigation efficiency is increased in a range of 5% to 15%. The subsurface drainage coefficient was estimated to be 1.09 mm/d whereas the design drain pipe capacity was estimated to be 2.2 mm/d, based on the peak discharge of the most critical crop (maize), rather than 4.0 mm/d which is currently used. A significant decrease of the drainage coefficient and the drain pipe capacity ranges from 18% to 45% was found with the increase of irrigation efficiency in a range of 5% to 15%. The leaching requirement for each crop was also estimated.  相似文献   

9.
The traditional approach ofinstalling subsurface drainage systems tosolve shallow ground water problems is notfeasible along the west side of the SanJoaquin Valley of California because of thelack of drain water disposal methods thatare economical, technically feasible, andenvironmentally friendly. Thus, optionssuch as drainage reduction through improvedirrigation and drain water reuse are beingexamined as methods for coping with thesubsurface drainage problem. This paperdiscusses options for reducing subsurfacedrainage through improved irrigationpractices. Options are discussed forimproving irrigation system design such asupgrading existing irrigation methods andconverting to systems with higher potentialirrigation efficiencies. Methods forimproving water management are alsopresented. Case studies on upgradingexisting systems or converting to otherirrigation methods are presented along with study results of the effect of variouspolicies on reducing subsurface drainage.  相似文献   

10.
In recent years, the traditional concept of an irrigation project has been changing. From just a physical structure for the storage, conveyance and distribution of water, it is now being regarded as a more complex system, including farmers' participation. This implies an improved management in all phases, from reservoir operation to farm management, and therefore the change from simple operation and maintenance to operation, maintenance and management.To face this new challenge, existing projects must be modernized. The Sorraia Irrigation Project is one of those projects. In this paper major problems are identified and it is showed how research (namely through modelling) can be oriented towards an improved management, regarding the conveyance and distribution systems as well as the on-farm systems.Finally it becomes evident that beyond the technical problems to be solved, the involvement and participation of farmers must be improved at all levels of management. Hence, there is also a need for implementing programs on education, training and extension.  相似文献   

11.
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 and Nepal is not an exception. 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. Khageri Irrigation System in the Chitwan district of Nepal was taken as the study site where complete management transfer has been done in 1996. The situations before and after complete transfer were compared. Intensive case studies of the selected farmers showed that equity in distribution of water and leakage had significantly improved after management transfer. Logit analysis revealed that age and education level of the household head, distance from main canal, leakage of the canal and equity in distribution are significantly related to the satisfaction level of the beneficiary farmers from FMIS compared to AMIS. However, landholding size of the respondent farmer has no significant effect. Similarly results from t-test revealed that rice productivity and overall profits from agriculture has also increased significantly due to irrigation management transfer.  相似文献   

12.
The non-uniformity of soils, weather, fields, cropping pattern and canal systems in most surface irrigation schemes makes irrigation water management complex, but optimum performance is important particularly in irrigation schemes with limited water supply. This paper focuses on the performance of irrigation water management during the area and water allocation with a case study of an irrigation scheme in the semi-arid region of India. Often the irrigation managers or authorities of these heterogeneous irrigation schemes also need to deal with different allocation rules. The allocation plans and the corresponding water delivery schedules during the allocation process were estimated with the help of a simulation–optimisation model for different allocation rules based on cropping distributions (free and fixed), water distributions (free and fixed-area proportionate), irrigation depth (full, fixed depth and variable depth irrigation) and irrigation interval (from 14 to 35 days). The performance measures of productivity (in terms of net benefits and area irrigated), equity (in water distribution), adequacy and excess were assessed for these different allocation plans and schedules. These were further compared with the performance measures of the existing rule (fixed depth irrigation at a fixed interval). The analysis revealed that these performance measures are in some cases complimentary and in other cases conflicting with each other. Therefore, it would be appropriate for the irrigation managers to understand fully the nature of the variation in performance measures for different allocation rules prior to deciding the allocation plans for the irrigation scheme.  相似文献   

13.
Studies of the performance assessment of irrigation schemes have gained momentum since the late 1980s due to the common perspective that the resources (land and water) in irrigation schemes are not being managed appropriately. 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 two types of allocative measures (productivity and equity) and five types of scheduling measures (adequacy, reliability, flexibility, sustainability and efficiency), together with the methodologies for estimating these for the scheme as a whole during different phases of irrigation water management.  相似文献   

14.
Irrigation system maintenance hastraditionally played second chair to systemoperations. This relative neglect hassquandered economic benefits and depletedthe value of capital assets. Recentprograms transferring operation andmaintenance responsibility to water usergroups offer an opportunity to redress thisbalance and create a more systematic andsustainable program of system maintenancein transferred systems. This paperidentifies important research needs thatform the basis for an action researchintervention program. The need to linkmaintenance inputs to hydraulic performance isclearly important, as is the need toprioritize inputs in terms of both cost andexpected impact on performance. Thefunding of maintenance is closely linked toasset management so that water user groupscan develop long-term strategies forprioritizing and financing theiractivities. Factors that lead water usergroups to choose between a self-helpstrategy towards O&M and the hiring ofprofessional staff to undertake these tasksalso requires additional research andinvestigation. Finally, the relationshipbetween regular maintenance and frequentrehabilitation needs to be defined and thetwo linked through policy, agreements, andfunding arrangements.  相似文献   

15.
The characteristics and potential of project management software as a tool for improved planning and management of on-going irrigation operations are assessed. A commercially available package was tested through use for the simulated planning of the close season maintenance campaign of major pump stations at a large scale irrigation scheme in Morocco. The software was found to be well suited to this planning activity and successfully helped resolve conflicts in terms of time and resources available. Its potential as a tool for sensitivity analysis and for monitoring and control was clearly demonstrated. The exercise had an immediate effect on management decision making and managers concerned have adopted the software for further trials. The approach is recommended as a means to enhance planning, communication and teamwork for suitable irrigation management operations, but will be most effective with the development of supporting databases to enhance the quality of planning data used.  相似文献   

16.
There exist capabilities for analyzing the behavior of surface flow and the ultimate distribution of infiltrated water in furrow irrigation. The corresponding synthesis, i.e., the selection of appropriate combinations of inflow rates, cutoff times and length of furrow — design and management, currently not so well established, is treated herein. A design-management nomograph is proposed for free draining graded furrows. This is a plot of efficiency, time of cutoff and uniformity coefficient contours each given on a length-flow rate space adjacent to one another, for a furrow with given infiltration characteristics, flow geometry, slope, roughness and required depth of application. The nomograph can be used to determine the combinations of length, time of cutoff and flow rate that would yield in optimum combination of efficiency and uniformity.  相似文献   

17.
In many countries today, irrigation systems have been transferred to the water user associations (WUAs). Accordingly, it is believed that the performance of the irrigation systems is dependent on the performance of the WUAs.In this study, the performance of participatory irrigation management (PIM) over time is assessed with regard to the Kestel WUA serving a wide area of Turkey's Aegean coast. Data relating to the WUA is obtained from both the State Hydraulic Works and WUAs’ own records. In addition, two surveys have been carried out with the members of the WUA with an 8-year interval between them. Data have been analyzed within the framework of selected irrigation performance criteria and indicators. The non-parametric Mann-Whitney U test was used to compare the perceptions of the farmers on the WUA at different survey periods. A Logit model was estimated to evaluate the relationship between the irrigation problems and the level of satisfaction from the WUA.The performance of the WUA with the indicators of utility, productivity, sustainability and financial efficiency was found to be positive; while the performance of adequacy was identified as poor. The farmers were generally satisfied of the WUA's operation, with their level of satisfaction improving over time. On the other hand, the farmers were not fully convinced that they had input with the system management. The initial design of the channel system and its maintenance were identified to be the key factors affecting user satisfaction.Overall, the Kestel WUA may be considered a successful example, thus supporting a promising future for PIM. Yet improved control and farmer education is needed for a superior performance of all indicators; and further enhanced farmer participation in management should be achieved in order to raise the level of farmer satisfaction.  相似文献   

18.
Timing of supply of irrigation water is an important measure of water management performance. Yet despite this widely accepted importance of timeliness, few studies have attempted to quantify this performance indicator. This paper suggests a methodology for quantifying timeliness. The indices thus generated are used to compare the performance of some types of smallholder irrigation schemes in Zimbabwe. Results indicate that applying measures of timeliness helps to assess water management practices across scheme types.The methodology given in this paper differentiates between timely irrigation deliveries which meet Crop Water Requirements (CWR) and surplus water supplies due to poor timeliness which cannot be used by the crop, hence denoting wastage. The timeliness indices provide more information regarding management practices than simple measures of total water applications over a given season.  相似文献   

19.
The use of measured water in controlling flows for the irrigation of sugarcane was found to be vital for the rehabilitation and management of surface irrigation on a 5000 ha sugarcane project. Methods of water delivery, measurement and control at Inyoni Yami Swaziland Irrigation Scheme (IYSIS) are described. Improvements to the irrigation, using existing methods of water measurement, were carried out over a period of four years. The lessons gained in this programme of improvements confirmed the benefits of using modulus gates which allow a constant, measured, discharge of water.  相似文献   

20.
The development of a role playing exercise for training of irrigation professionals in the management of small holder irrigation schemes is described. The exercise places participants in the position of either agency staff or farmers. As farmers participants are dependent on irrigation water supplies from the agency managed run-of-the-river irrigation system. As agency staff participants are responsible for water allocation between competing demands on the main system. The exercise develops interaction between the participants as they trade in water and negotiate for irrigation supplies.The exercise develops an understanding of the issues involved in managing an irrigation system, though not only on technical matters such as water allocation policy, yield response to water and performance assessment. The exercise also creates an awareness of the whole system, in particular the importance of communication between agency staff and farmers, and between farmers themselves.The Irrigation Management Game is the copyright of the author, Professor Ian Carruthers of Wye College, University of London and consulting engineers Mott MacDonald, Cambridge, UK.  相似文献   

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