Therefore, only eight months in each year are suitable for construction work, and it takes great effort to prevent loss of construction materials and equipment when flash floods occur.
高速公路沿線的地形、地質、天候環境，南北各異，所以施工遭遇的困難也迥不相同。通往基隆的大業隧道，由於基隆多雨，土質不好，工程進行十分艱難。