Abstract：The total tunnel length of the longest hydraulic tunnel in Taiwan，the New Wuchieh Diversion Tunnel and Lishi Creek Diversion Project of Taiwan Power Company，is about 16.5 km. Considering the homogeneous rock condition without obvious poor geological structures，the 7.8 km long tunnel between the Ghoshui River Crossing Bridge and the Muchilan Culvert is excavated by the TBM (Tunnel Boring Machine). TBM tunneling can not only shorten the construction period，but also lower the impact to the environments，requiring less labor and improving the tunneling technique of Taiwan. During the construction period，a serious earthquake and a heavy typhoon had been encountered. With proper measurements and treatments，the excavation of the TBM is very smooth. On June 7，2002，the tunnel was broken through by TBM. This is also the first successful break-though of TBM tunneling in Taiwan. The average monthly progress of 315 m and the biggest driven length of 6 523 m by TBM became a new milestone in Taiwan.
2004, Vol. 23 
