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Guide to Authors. It is one of densely populated state in Africa where the total population is about 9million, resides in the total surface area, 26,km 2. For nearly two and half decades Rwanda has been facing problems of food security. This trend was exacerbated by the sad events of genocide and war of the mids.
The productivity from these farms is low due to continued land degradation by erosion and low utilization of fertilizers and other agricultural inputs. Marshlands are estimated at , hectares from which only the half has been exploited so far for agricultural purpose. However, the pattern of exploitation of these swamps is more towards traditional methods because of lack of appropriate technology. Hitherto, inappropriate and inadequate exploitation of swamps in Rwanda has led to their irreversible degradation and continuously declining soil productivity.
Faced with the above problems the Government has instituted several measures to address them. One of which is the Green Revolution. Under this a number of pathways are being pursued in order to address food security, reduce poverty, maximize crop production per unit area and improve the quality of life of the rural people.
Crop production under smallholder irrigation is seen as one of the means to implement the Green Revolution. With the objective of improving food security, the Local Authority would like to reduce the water losses, expand the area under smallholder and improve on the efficiency of irrigation and thus maximize water use efficiency and land productivity. Main problems and constraints faced in on-farm irrigation management are inefficient water use, high cost of irrigation systems and quality of irrigation equipment.
Excessive amount of irrigation water has been used in the existing traditional surface irrigation. The performance of irrigation and drainage is critical to the food supply and to farmers incomes, as well as to the environment. The ultimate goals in managing irrigation water are efficiency, equity and sustainability.
Efficiency has been achieved if every drop of water has been properly allocated and used, without any waste. The goal of equity means that water is fairly distributed among users. Some farmers may have an advantage over others. Those at the head of a canal have an advantage over those living downstream, as they have first access to water.
Influential farmers may have better access to water than poor farmers. In some cases, ideals of efficiency and equity may be in conflict. The goal of sustainability means that the users of today should maintain the quality and quantity of water resources for the use of future generation. Participatory irrigation management can offer one way of improving water user efficiency. Irrigation increases crop production by increasing crop yield cropping intensity and making possible cultivation of high value and remunerative crops.
For obtaining optimum yield, water should be provided in time and in adequate quantity according to the water requirement of the crops at their various growth stages. This transfer envisages that farmers should be involved in various aspects of management of irrigation system, particularly in water distribution and collection of water rate, operation and maintenance of irrigation structure. Main problems and constraints faced on farm management of COCURIRWA are the management of water collection fees, identification of costs and benefits, quantification of costs, the comparison of costs and benefits which result in high costs of irrigation system and quality of irrigation equipment.
Management of the water resources for diverse uses should incorporate a participatory approach: by involving not only the various governmental agencies but also the users and other stakeholders, in an effective and decisive manner, in various aspects of planning, design, development and management of the water resource schemes. Necessary legal and institutional changes should be made at various levels for the purpose, dully ensuring appropriate role for women. The first phase of this project had been started in in the area of ha for rice production.
The production was of great efficiency from to but decreased in due to lack of financial resources, improper water management and also the decrease of soil fertility.
However the productivity increased in by the loans from Rwandese Ministry of finance. The project restarted from the end of year by the government of Rwanda which encouraged the survivors of the war to go on. In these days, the rice project is getting extended in other districts of East Province such as Kayonza, Kirehe and Gatsibo, hence total area to be exploited is estimated to be ha. The temperature and precipitation data are shown in the following Table 1.
Table 1 Temperature and precipitation Source: Meteorological department, Rwanda. Managing irrigation so as to achieve efficiency, equity and sustainability is very difficult. Agricultural product marketing opportunities are not enough. High prices for water when it is scarce mean that low-income users may lose their access to water.
Unrestricted use if prices are low may lead to pollution, water logging and over-use of groundwater.
Given the special characteristics of irrigation water, there is good reason for governments to intervene and even directly manage irrigation systems. However, when a centralized agency is in charge of planning and operating an irrigation system, the result is often too much bureaucracy. Too much money is spent on staff salaries.
As a result, the cost of water is high and yet the irrigation service is poor. Users are unwilling to pay their irrigation fees. The result is a vicious circle of high costs, poor services and low payment of fees, leading to inadequate funding and further deterioration of services.
One way out of this difficult situation is the participatory approach to irrigation management. Users are involved at all levels, including construction and operations. It seems to give greater efficiency at a lower cost. The term Participatory Irrigation Management PIM refers to the participation of users the farmers in all aspects of irrigation management and at all levels. All aspects include planning, design, construction, operation and maintenance, financing, decision rules, Monitoring and Evaluation of the irrigation system.
PIM processes build two forms of capital: productive capital better maintained irrigation infrastructure and social capital new institutions such as WUAs, skills, leadership and community action. It is unlikely that full cost recovery will be reached without formal and effective participation of all users in the management of irrigation projects.
In Rwanda, swamps are reservoirs of water and irrigated agriculture in swamps is an important water consuming activity. Rwamagana swamp located in eastern province faces an improper management of water, the lack of link between water users and different stakeholders and the non existence of a participatory irrigation management organization for better water use which lead to decrease in productivity.
However, the sources of water in Rwamagana swamp can supply enough water for the entire developed area of the whole project during the dry season. Water misdistribution occurs over the secondary and primary canals of Rwamagana irrigation system. This misdistribution results in major differences in water availability from one tertiary unit to another. Generally the tail end portions have serious deficiencies of water whereas the head of upper sections have excess water resulting in decrease of productivity in a major part of the rice perimeter resulting permanent conflicts between farmers and even some plots are cultivated once a year.
There is a need of achieving an equitable water distribution by controlling the flow distributed in the laterals and the turnouts for the cropping activities and the respective water requirements of them through a "new social contract for water" Rwamagana swamp which is managed by COCURIRWA cooperative there were a poor management of irrigation resulting in poor productivity.
Comparison of benefits with costs can give a reliable idea about the relative importance of the investment in the PIM program. The main objectives of this study is to bring out the quantum of costs and the benefits against the project cost over a period of time and thus verify the hypothesis that benefit cost ratio of PIM is positive. There are 2dams provided for the purpose of irrigation system i. The drainage system is enabled by one main canal of 22km length, which is constructed at the lowest point in the middle of rice cultivation.
Watergates, subsidiary storage, sluices, aqueducts footbridges are also provided. This site uses three dams:. This site has been recently extended. The presence of much water and also the exploitation infrastructures which have been maintained are remarkable. For every dam, a number of sub-barrages are provided along the main drain at different distances from the reservoir. The water from the paddy field is collected into the main drain it is arrested by the sub-barrage at a considerable distance of dam in order to enable the good irrigation for the following paddy field.
So, the sub-barrages provided on main drain are useful for raising the level of water for good irrigation of field which is so far away from the dam and difficult to use irrigation canals already constructed. There is a main river flowing along each site where water comes out during heavy rainy season. The average slope of Gitinga is 2. The length of Mwambu irrigation area is The average slope of Mwambu region is 2. Water requirement may be defined as the quantity of water regardless of its source required by a crop in a given period of time for its normal growth under field conditions at a place.
It includes the loses due to evapotranspiration plus loss during the application of irrigation water unavoidable losses and the quantity of water required for special operations such as land preparation, transplanting, leaching, etc.
Cost recovery for irrigation system maintenance is low, with the assessed water use charges or abiana themselves not reflecting the cost of service provision on the order of Rs.