Urban Planning Act Article 50

Land reserved for public facilities may be used for construction of temporary buildings by application before it is obtained for the planned purposes.When notified by the local government that the construction of public facilities is to commence and the said buildings must be dismantled within a given period, the owners of the temporary buildings described in the preceding paragraph must comply unconditionally. Otherwise, compulsory dismantling shall be enforced.The Ministry of the Interior shall stipulate the regulations regarding the use of temporary buildings on land reserved for public facilities in urban plans.
中文原文 都市計畫法第50條
公共設施保留地在未取得前,得申請為臨時建築使用。
前項臨時建築之權利人,經地方政府通知開闢公共設施並限期拆除回復原狀時,應自行無條件拆除;其不自行拆除者,予以強制拆除。
都市計畫公共設施保留地臨時建築使用辦法,由內政部定之。

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