Performance Enhancement of a Minor Irrigation System through Secondary Storage and Multiple Use Management

Abstract

In the process of irrigation development, minor irrigation systems have received equal importance with that of major and medium irrigation systems due to several advantages such as small capital investments, less gestation period, better flow control, farmers' friendly etc. In recent years, attention is being paid to rehabilitate the defunct minor irrigation systems to have better availability and distribution of irrigation water in the command. In the rehabilitated systems, it is expected that there will be better availability and distribution of irrigation water in the command both in the monsoon and dry season. In reality, in spite of increase in cropping intensity and irrigation intensity in the post rehabilitation period, there exists ample scope to enhance the crop coverage during dry season. Therefore, ways and means to augment the water resource scenario in the minor irrigation system is highly essential to bring the entire command area under crop coverage during dry season. Often, government assume that the transfer of management responsibility to farmer organizations will improve the accountability of the irrigation service to farmers, make the service more cost efficient, motivate farmers to invest more in maintaining irrigation systems and, ultimately, make irrigation systems and irrigated agriculture more sustainable. These expectations may not be always realistic. To address some of these problems, a study was conducted in a turned over minor irrigation system, results of which are documented here. The study envisaged in establishing the concept of secondary storage reservoir in the outlet command of flow based minor irrigation system to harvest rainwater during monsoon and store excess irrigation water, and utilizes the harvested water during the dry season most effectively. The technique of multiple use management of harvested water in the secondary storage reservoir though pisciculture and dry season crop cultivation was established. The effectiveness of WUA's functioning in creation, operation and maintenance of the system was also studied and ways and means to improve their effectiveness and sustainability were suggested. Hopefully, the outcome of the study will help policy planners, field engineers and farmers in formulating their strategies and preparing their plans for improving the irrigation and thereby the crop performance scenario in the irrigated command.