Whereas the irrigation water transmission open channel network in Egypt, is one of the largest and longest networks all over the world that dogged in permeable soil (Its length reaches about 33500 km). In a country that suffers greatly from an increasing shortage of limited available irrigation water quantities, ignoring the expected huge quantities of irrigation water losses through transport operations is a path of madness, to bridge the accelerated gap between what is required, and what is exist. Irrigation water conveyance losses include seepage, evaporation, and transpiration losses. The used data in this research was collected from the field and through the official Ministry of water resources and irrigation authority in Assiut governorate. The analysis of the data proved that, the total loss of irrigation water from Almanna canal and its branches reaches about 16.05 Million cubic meters monthly. The lost water through only seepage reaches about 15.95 Million cubic meters monthly, representing 99% of all lost irrigation water. While, the rate of increase in the evaporation losses at earthen sections more than the designed sections losses can be neglected. Thus, the lining of Almanna canal and its branches is the most effective solution for saving such a huge amount of water, and directed it to irrigate some newly reclaimed areas, in addition, to solve the problems of non-arrival of the irrigation water to the ends of some irrigation canals. At the same time, improving the environmental situation of the surrounding agricultural community.