Improvement of Water Use Efficiency and Remote Sensing Applications for Surface Soil Moisture Monitoring

Water is the most essential commodity for human beings to be alive and so it is very necessary to make proper use of water without wasting it. Irrigation sector is the biggest consumer of water as more than 80% of available water resources in India is being presently utilized for irrigation purposes. However, the average water use efficiency of irrigation projects in the country is assessed to be only of the order of 30 to 35%. In the north eastern region also, performance of the existing irrigation schemes (particularly, the major and medium irrigation schemes) suffer from low water use efficiency, distribution losses, poor operational maintenance and management and non-availability of water in the tail ends. The region has unique geographical, topographical, climatological settings and sociological characteristics, which are also influencing factors of low water use efficiency. Again, water demand for various purposes namely irrigation, drinking, domestic, power, industrial and other uses is increasing day by day leading to severe seasonal stress on water resources in the region. Its scarcity is more pronounced with increasing population and needs. In this paper the water use efficiency of the Sukla Irrigation Project is calculated as per methodology given in the guidelines for computing the Water Use Efficiency of the Irrigation Projects, CWC, February 2014. It has also been attempted to analyze the scope of improvement of the water use efficiency of the same. The water use efficiency of the project under existing condition was found to be 33.54%. The results reveal that management interventions of converting unlined canal sections into lined canal sections under practical achievable conditions can improve the conveyance efficiency (a component of water use efficiency) up to 75%. As a result, an amount of about 16 Mm3 water can be saved from which about 2673Ha additional area can be irrigated. With very good level of maintenance the conveyance efficiency can be further enhanced to 95%. This will lead to saving of 53 Mm3 of water from which about 8794 Ha of additional area can be irrigated. This paper also presents a review of the progress in remote sensing of soil moisture, with focus on technique approaches for soil moisture estimation from optical, thermal, passive microwave, and active microwave measurements.