Water Act Article 25
The authority-in-charge may reassign water right according to the prevailing usage when joint owners of a water right have a dispute over water usage.
中文原文 水利法第25條
共同取得之水權，因用水量發生爭執時，主管機關得依用水現狀重行劃定之。
English translation for reference only; the Chinese text prevails. Not legal advice.