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INDUS BASIN IRRIGATION SYSTEM
A recent example of the development process described above, which also serves to alleviate salinity problems in waterlogged areas, is the On-Farm Water Management Development Project (OFWMDP) which was implemented in the Indus Basin in 1976 (Skogerboe, Kemper and Reuss, 1980). Pakistan has one of the world's largest contiguous irrigation systems with water from the mighty Indus and its tributaries serving approximately 13 million hectares of land (Figure 6). In most of this area, irrigation is a prerequisite of crop production. The original irrigation system was built to command more land area than could be irrigated by the water diverted from the Indus River and its tributaries. During any particular season the farmers are normally irrigating and cropping about 60 per cent of their land area. Consequently, additional water delivered to the farmer's field can generally be utilized and translated into more acres cropped and harvested.
A modern irrigation conveyance system was first constructed in Pakistan by the British in the late 1800s. About 10 million hectares actually receive surface water. Today there are more than 100,000 tubewells supplementing the Indus system and over 200,000 persian wheels which also provide supplemental water. There are about 3 million individual farms with a median size of 2.1 hectares. This probably constitutes the greatest single agricultural potential in the world.
Figure 6. Indus Basin Irrigation System
Pakistan has over 80,000 watercourses with an average cultivable command area of 162 hectares each. This means that the average watercourse serves 40 farmers and that a normal village of 100 to 120 farms will have approximately three watercourses. Since watercourse command areas are topographically determined and land ownership is not, it can happen that one watercourse serves land owned by farmers in different villages. Conceivably, either the watercourse or the village could serve as the basic organizational unit for a water management programme.
Method of Irrigation
The irrigation system is so constructed that water flows from the minor canals through turnouts (moghas) supplying water to a village area. The farmers themselves operate and maintain their distribution system. There are no headgates at the moghas and if a particular canal has water in it, there is water in every watercourse (khal) on that canal. The farmers on the watercourse use the entire flow in turns based on farm size, and each has a fixed time each week, ten days, or two weeks to use this water. This system of rotation is called a warabundi.
The topography of the Indus basin is flat. The general slope downstream averages from about nine inches to one foot per mile. Natural drainage ways are not readily apparent. Practically no artificial drains have been constructed, therefore surface drainage for irrigation water is virtually nonexistent either from artificial or natural drains. Irrigation water passing through each mogha, as well as surface runoff during the monsoon season, is therefore utilized on that particular watercourse area as there is no provision to let it pass to an area of lower elevation.
The inundation or level basin system of irrigation is used extensively in Pakistan. The flat topography might suggest this practice but actually the constraints are such that no other system is possible. The non-runoff restriction requires either a system in which water is applied precisely according to the infiltration rate or it must be ponded. The low infiltration capacities of most soils make it impossible to get sufficient water into the soil profile during one irrigation turn. The level basin system has been utilized because it exactly fits these resources and constraints. Furrow irrigation is practiced with some crops and it is interesting to observe that the furrows are constructed to provide for a great deal of storage. The ponding method, then, is also used with this system; the furrow is made very broad and will store sufficient water to fill the soil reservoir even though infiltration rates require that the opportunity time be much longer than the warabundi turn.
Unlined Watercourse Channels
In most watercourses, losses can be significantly reduced by providing the channels with proper design specifications (cross section, slope, etc.); replacing the permeable side banks with fresh compacted soil; and installing concrete outlets. This type of improvement uses relatively little capital and can utilize labour that is available during slack periods of the year. In the watercourse rebuilding projects conducted to date, farmer communities have been selected that can speak for all the water users and mobilize labour as needed. With forty or fifty independent farmers, coming from as many as ten different brotherhood groups (biradris), organizing farmers is no easy task. The earliest earthen watercourse improvement programmes were in villages that had demonstrated a capability for co-operative efforts. Later, watercourses were purposely selected in village areas that had a high rate of litigation and crime, such as robberies and kidnapping. However, once convinced of the value of watercourse improvement, farmers have shown a surprising willingness to form committees and make improvements on their watercourses. The costs of these improvements were approximately Rs. 6.5/metre (Reuse, Skogerboe and Merrey, 1980).
At the same time that the technology for earthen watercourse improvement was being developed, the US Soil Conservation Service (SCS) was developing a precision land levelling (PLL) programme with the provincial Department of Agriculture in both the Sind and the Punjab. Such a programme had proved highly successful in Turkey. A training course was-established in both provinces that provided the necessary skills for Agricultural Science graduates to completely implement a field programme.
The Government of Pakistan (GOP) and the US Agency for International Development (AID) decided to combine watercourse improvement and precision land levelling into a single programme to be initiated as a pilot project on 1,500 watercourses. In addition, 10 to 30 per cent of the watercourse would be lined with brick-and-mortar in waterlogged areas to alleviate salinity problems. This pilot project was to be implemented in all four provinces.
The general objective of the on-Farm Water Management Pilot Project (OFWMPP) is to increase food production and farm incomes by increasing the efficiency of water management on farms and in the watercourse delivery systems of Pakistan with a secondary objective of alleviating salinity problems in waterlogged areas.
Setting a target of a minimum acceptable irrigation efficiency level for watercourses that have completed their programme was considered fraught with danger, since the construction of physical improvements only provides the potential for increased water use efficiency; the operation of the watercourse and irrigation practices largely dictate the watercourse irrigation efficiencies that will actually be achieved, the degree that groundwater levels will decline, and the reduction in soil salinity concentrations. This again indicates the importance of a well-trained water management extension staff for properly advising farmers on improved irrigation practices in order to more nearly achieve full benefits from the physical improvements. This implies that the general objective of increasing crop yields and cropping intensity, as well as reducing soil salinization, can be tackled using the following two derived objectives:
(1) To transmit to farmers knowledge of plant-soil-water
relationships necessary to plan and manage an efficient irrigated
cropping system to improve yields and cropping intensity;
(2) To transmit to farmers the techniques and knowledge necessary for efficient water control in watercourses and improve irrigation practices on farm fields.
In fact, the pursuit of these objectives in combination with the physical modifications of watercourse improvement and precision land levelling results in an optimum water management programme for both crop production and salinity control.
Several institutional objectives were considered necessary to ensure that physical changes would lead to an era of modern irrigation water management. These institutional objectives, if met, provide for a continuing stream of irrigation information research, its transfer to farmers, the development of a water management support industry, and the organization of farmers into units that can exert collective action on water affairs. The institutional objectives are:
(1) To develop a core of water management advisory (extension)
personnel trained in modern irrigation techniques whose services
would then be concentrated on the improved project watercourses;
(2) To develop a cadre of well-trained engineers and agriculturalists for the precision land levelling programme capable of performing design, layout, construction and evaluation;
(3) To develop a cadre of water management engineers trained in watercourse improvement and able to design and implement such a programme;
(4) To develop a research programme on crop irrigation and water management that will continue as a permanent part of the national agricultural research effort;
(5) To strengthen the linkages between research and extension and the farmer;
(6) To develop a network of water users associations enabling farmers to act collectively on their water management programmes and to aggregate and transmit a consensus regarding specific problems to levels of decisionmaking authority;
(7) To encourage private entrepreneurs throughout Pakistan to manufacture and market the several types of water management equipment that might be profitably used by farmers.
Monitoring and Evaluation
The Water and Power Development Authority (WAPDA) has been designated by the GOP as the agency responsible for the monitoring and evaluation of the OFWM project. The overall objective of the programme is to provide systematic feedback to enable effective and objective evaluation of the On-Farm Water Management Development (Pilot) Projects in the provinces. This evaluation concerns the overall effectiveness of the programme in saving water and increasing productivity and income and not the internal programme operations. The effective evaluation of this programme is a critical need for decision-making concerning future investments in water management projects. WAPDA presently has a trained group of people that have been engaged in a two-year survey of 61 watercourses, who are now available to undertake the monitoring programme.
The evaluation programme will be based on a sample of 40 improved watercourses which will be studied prior to improvement and on a periodic basis after improvement to determine changes in water delivery, crop production and socio-economic indicators. Some of the more important physical parameters to be measured are: land use, crop yields, cultural practices, irrigation practices, salinity status, water losses and application efficiencies, cropping patterns, crop loss due to spillage and leakage, and farm and crop budgets.
Social information collected will include such things as kinship and biradri (brotherhood) groups, land ownership, tenure types and distribution on the watercourse, leadership characteristics, and patterns of social polarization or conflict. Data to be collected within six months after improvement and on a recurring basis (probably 24-month intervals) will include: conveyance and application efficiencies, land use, crop acreage, crop yield, labour employment, water users association performance, adequacy of maintenance, farmer participation, and project communication effectiveness.
Water Users Associations
There is a growing literature on the problems of organization of irrigation systems (Hunt and Hunt, 1976). Unfortunately, there are very few studies of rural social organization and the organization of irrigation in Pakistan. During the past few years some research, mostly confined to Punjab, has begun to be published. The available studies focusing on the local organization of water management include Mirza (1975); Lowdermilk, Clyma and Early (1975); Lowdermilk, Freeman and Early (1978); Freeman and Lowdermilk (1978); Radosevich (1975); Mirza and Merrey (1978); and Merrey (1979). All of these studies demonstrate not only that present patterns of farmer organization and co-operation are totally inadequate to promote improvement, but that without a major effort to build farmer organizations as an integral part of the OFWM Project, this project is likely to fail.
The planners of the OFWM Pilot Project, being acutely aware of the importance of farmer organization, envisioned studies and experiments of farmer organization as an integral part of the project. A basic principle of the present OFWMDP is that there must be the maximum possible participation by the farmers in the project. The greater their level of participation, the greater will be their commitment to the subsequent maintenance of the improved watercourse. However, this participation should extend beyond contributing money and labour to the project. Farmers should also be involved in the decision-making process.
An evaluation of the On-Farm Water Management Pilot Project was recently undertaken. This evaluation showed that although the target number of watercourses had not been completed, the farmers were highly receptive to the programme and were placing great demand upon the field teams to undertake many more watercourses. Farmer interviews showed that most field personnel had gained credibility with the farmers far exceeding any other government programme. Also, the capability of the field teams is rapidly expanding. Presently, the governments of Canada, the United Kingdom and the Federal Republic of Germany, as well as the World Bank, are exploring possibilities for expanding this village-level programme to all of Pakistan's more than 80,000 watercourses.
Freeman, D. K. and Lowdermilk, M. K., 1978, "Sociological Analysis for Irrigation Water Management-A Perspective and Some Analytical Approaches to Assist Decision Making". Improving Water Management on Farms, Appendix 34; Annual Technical Report. Fort Collins: Water Management Research Project, Colorado State University.
Hunt, R. S. and Hunt, E., 1976, "Canal Irrigation and Social Organization". Current Anthropology, Vol. 17, No. 3, pp. 389-411.
Lowdermilk, M. K., Clyma W. and Early, A.C., 1975, "Physical and Socio-economic Dynamics of a Watercourse in Pakistan's Punjab: System Constraints and Farmers' Responses." Water Management Technical Report No. 42. Fort Collins: Colorado State University.
Lowdermilk, M. K., Freeman, D. K. and Early, A. C., 1978, "Farmer Irrigation Constraints and Farmer's Responses: Comprehensive Field Survey in Pakistan." Joint contribution of Colorado State University and Directorate of Watercourse Chak Farming Survey Project. Lahore: Survey and Research Organization, Master Planning and Review Division (WAPDA).
Merrey, J., 1979, "Irrigation and Honour: Cultural Impediments to the Improvement of Local Level Water Management in Punjab, Pakistan." Field Report No. 9. Lahore: Colorado State University Water Management Research Project in Pakistan.
Mirza, A., 1975, "A Study of Organizational Factors Affecting Water Management Decision Making in Pakistan." Water Management Technical Report No. 34. Fort Collins: Colorado State University.
Mirza, A. and Merrey, J., 1978, "The Water User Association Research Project: An Interim Report." Faisalabad: Agricultural University (Cyclostyled). Also published in: Annual Report, Water Management Research Project, Colorado State University, Fort Collins, June, pp. 540-586.
Radosevich, G. E., 1975, "Water User Organizations for Improving Irrigated Agriculture: Applicability to Pakistan." Water Management Technical Report No. 44. Fort Collins: Colorado State University.
Radosevich, G. E. and Skogerboe, G. V., 1977, "An Influent Control Approach to Irrigation Return Flow Quality Management." Proceedings of National Conference on Irrigation Return Flow Quality Management, Colorado State University, Fort Collins, May 16-19, pp. 423-434.
Reuss, J. O., Skogerboe, G. V. and Merrey, D. J., 1980, "Watercourse Improvement Strategies for Pakistan." International Journal of Water Supply and Management, Vol. 4, pp. 409-422.
Skogerboe, G. V., 1974. "Agricultural Systems." In Human Ecology. Chap. VII, pp. 127145, North Holland Publishing Co., Amsterdam.
Skogerboe, G. V. and Law, J. P., Jr., 1971, "Research Needs for Irrigation Return Flow Quality Control." Report No.13030-11/71, US Environmental Protection Agency, Washington, DC.
Skogerboe, G. V. and Walker, W. R., 1980, "Impact of Irrigation on the Quality of Groundwater and River Flows". In Impact of Salinity on Water Resource Use and Development. Marcel Dekker, Inc., New York.
Skagerboe, G. V., Walker W. R. and Evans, R. G., 1980, "Modelling Water Quality from Irrigated and Rainfed Agricultural Lands." In Application of Ecological Modelling in Environmental Management. Pergamon Press, Oxford.
Skogerboe, G. V., Walker, W. R. and Evans, R. G., 1979,"Environmental Planning Manual for Salinity Management in Irrigated Agriculture." EPA-600/2-79-062. Robert S. Kerr Environmental Research Laboratory Office of Research and Development, U.S. Environmental Protection Agency Ada, Oklahoma, p. 233.
Skagerboe, G.V., Lowdermilk, M. K., Sparling, E. W., and Hautaluoma, J. E., 1980, "Development Process for Improving Irrigation Water Management of Farms: Executive Summary." Water Management Technical Report No. 65A. Water Management Research Project, Colorado State University, Fort Collins.
Skogerboe, G. V., Kemper, W. D. and Reuss, J. O., 1980, "Development of Improved Water Management Practices in Pakistan." International Journal of Water Supply and Management, Vol.4,pp.299-312.
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