Urban Planning Act Article 29

The Ministry of the Interior and local governments at all levels or township and county-administered city offices may send personnel to conduct investigations and surveys on all public and private land for the establishment, formulation or modification of urban plans. However, to enter land that is fenced off or blockaded, the said personnel shall notify the owner or user in advance.If removal or elimination of obstacles is required for the land investigations and surveys described in the preceding paragraph, the owner or user of the land must be notified in advance and appropriate compensation shall be made for any damages there of incurred. Both sides shall negotiate to determine the amount of compensation. If both sides fail to reach consensus, the concerned special municipality or county/city government shall request the Ministry of the Interior in writing to make the decision.
中文原文 都市計畫法第29條
內政部、各級地方政府或鄉、鎮、縣轄市公所為訂定、擬定或變更都市計畫,得派查勘人員進入公私土地內實施勘查或測量。
但設有圍障之土地,應事先通知其所有權人或使用人。
為前項之勘查或測量,如必須遷移或除去該土地上之障礙物時,應事先通知其所有權人或使用人;其所有權人或使用人因而遭受之損失,應予適當之補償;補償金額由雙方協議之,協議不成,由當地直轄市、縣(市)政府函請內政部予以核定。

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