Water Act Article 20-1
When water is under supply, the water right holder who is given preemptive use on account of his priority according to subparagraphs 2 ~ 6, paragraph 1 of Article 18 herein shall properly compensate water right holders who have registered their water right before he did, provided his preemptive use causes material damages to those water right holders. The amount of compensation is subject to the agreement of parties concerned. If no agreement is reached, the authority-in-charge will assess the damages and approve the amount, and impose the liability upon the one who has the preemptive use.
中文原文 水利法第20-1條
水源之水量不足，依第十八條第一項第二款至第六款用水標的順序在先，取得水權登記在後而優先用水者，如因優先用水之結果，致登記在先之水權人受有重大損害時，由登記在後之水權人給予適當補償，其補償金額由雙方協議定之；協議不成，由主管機關按損害情形核定補償，責由優先用水人負擔之。