Water Act Article 52

When it is necessary to construct dams or gates on navigable waterways for a water work, lock gate shall be built at suitable locations. The number, size, and schedule for opening and closing the lock gate shall be prescribed by the authority-in-charge according to actual needs.The proprietor shall bear the costs and expenses of building the lock gates under the preceding paragraph. If the depth of navigable waters increases due to the construction of a dam, the authority-in-charge may, after considering the nature of the navigable waters, subsidize the costs and expenses of the construction after approval by its superior authority.
中文原文 水利法第52條
在通航運之水道上,因興辦水利事業,必須建造堰壩、水閘時,應於適當地點建造船閘;其數目大小及啟閉之時間,由主管機關依實際之需要規定之。
前項建造船閘之費用,由興辦水利事業人負擔。
但航道之深度,因建造堰壩而增加時,得由主管機關視水道之性質,報經上級主管機關核准,予以補助。

English translation for reference only; the Chinese text prevails. Not legal advice.