ABSTRACT
From the time immemorial, gravity irrigation by way of flooding in furrows and various forms of basins has been practiced all over the world. In surface irrigation, water infiltrates into the soil while traversing and also while standing in the furrows, borders or basins. The depth of infiltration depends on the quantity, duration and rate of stream flow, the gradient, soil texture and structure. The overall irrigation efficiency in surface irrigation varies from 25 to 60%, and is considered low because of water loss due to seepage, evaporation and deep percolation. Additionally, it may cause erosion, salination and water logging. Because of low irrigation efficiency, larger quantities of water are required to carry it from the source to field, calling for greater storage facilities and channel capacities, larger structures and extensive drainage systems.
