Water Act Article 20

When dispute arises among registered water right holders due to under supply of water, the holder who has a higher priority of usage shall be given the preemption; among those who have the same priority, the holder who acquired the right first shall be given the preemption; among those who have the same priority and acquired their rights at the same time, water shall be used on a pro rata basis according to the quantity stipulated on their respective water right deeds or by rotation. The rules for preemptive use of water shall be promulgated by the central authority-in-charge.