Basins can be flat, either sunken or raised, or ridged. In all cases good basin irrigation requires the ground surface to be level
Chidikha chikhoza kukhala cha thyathyathya, cholowa pansi kapena chokwezedwa, kapena cha mizere. Mu zonsezi, mthilira wamuchidikha umafuna pamalo pakhale posatsetsereka