Details of levy clause of constructional advantage Article 21

For overlapping benefited surfaces of concurrent projects due to narrow distance between two adjacent roads, the central line of the overlapping part shall be the dividing line with the area on each side of the line included in the calculation of the benefited surface of the respective project.In the event that after the cut by the dividing line Zone 2 or Zone 3 area becomes so small that the unit charge imposed thereon becomes higher than that on Zone 1 or Zone 2 respectively, the relevant government shall adjust it downward in proportion to the fee-sharing percentage of the respective zones.
中文原文 工程受益費徵收條例施行細則第21條
臨近道路距離過小而同時辦理之工程,致受益面發生重複時,就其重複部分之中線劃定等分線,各就其等分線之間所包括之土地面積,計算其受益面。
前項等分線劃定後,若發現第二區或第三區面積過小,致徵課單價高於第一區或第二區時,應由各級政府酌情依比例從低調整。

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