ABSTRACT
Theobjective of an irrigation canal is tomeet the varying irrigation requirements during the irrigation season at the individual farms and therefore the canal design should preferably be based on the following criteria: • Capacity: the capacity of an irrigation canal depends on the water
delivery method. The delivery methods differ from each other through the scheduling of the water supply in time and place. The World Bank (1986) classifies the following delivery methods: – on demand: the water delivery reacts instantaneously to the water
demand; – continuous: the irrigation canal supplies a continuous, either constant
or varying, but continuous flow during the whole irrigation season; – fixed rotation: the water delivery is scheduled with a constant flow
and a regular pattern of rotation; – variable rotation: the water delivery is programmed either for a fixed
supply with variables periods (rotation) or for a variable supply and variable periods.
