Maritime Act Article 68

Where the ship during voyage encounters a disaster or becomes incapable of navigation yet the cargo are eventually carried to the port of destination by the shipmaster, and the freight payable thus becomes lower than the freight previously agreed upon, the shipper shall pay the freight with a deduction of one half of the difference between the two freights.If the new freight is the same in sum as the freight previously agreed upon, the shipper shall bear no obligation to pay any additional expenses. If the new freight is higher than the freight previously agreed upon, the balance is to be borne by the shipper.
中文原文 海商法第68條
船舶在航行中遭難或不能航行,而貨物仍由船長設法運到目地港時,如其運費較低於約定之運費者,託運人減支兩運費差額之半數。
如新運費等於約定之運費,託運人不負擔任何費用,如新運費較高於約定之運費,其增高額由託運人負擔之。

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