TAIPEI (Taiwan News) — To protect the water supply for 6 million people in the Greater Taipei area, a special NT$2.5 billion (US$82.5million) water pipeline was funded by the Taipei City Government, per UDN.
The project was arduous, requiring traditional tunneling machinery for the excavation of the entire line. After completion, Taipei residents can expect better water quality with less turbidity or muddy sediment in their drinking water.
Following typhoons, reservoirs suffered from water turbidity, sometimes appearing with a yellow mud tinge which made water treatment more challenging. Furthermore, over-development of areas around the Nanshi Rive has led to water and soil conservation issues for decades.
Former Taipei Mayor Ko Wen-je (柯文哲) received funding from the national government’s Forward-looking Infrastructure Development Plan to build a water pipeline from the Fetsui Reservoir.
This water pipeline consists of an underground tunnel with a diameter of about 5 meters. Workers faced an arduous task drilling the tunnel into hard rock, requiring four years of excavation, with less than 10 meters left to be penetrated.
Every day, an average of 30 workers use drilling machines to drill holes in hard rock walls, breaking them into smaller pieces, and then using an excavator.
Every time they dig 1 meter, they have to use the steel support frames to prevent the walls from collapsing. The walls of the excavated tunnel are sprayed with mud by a spraying machine.
The length of the pipeline is 2.8 kilometers with construction taking place day and night, with daily progress the equivalent of just 1 meter per day.
The geology around Xindian is hard shale. Blasting can speed up the progress of the project. However, in order to avoid impacting the environment and ecology around the Feitsui Reservoir, blasting work on the tunnel was prohibited.
Because the rock plates are too hard, the drill bits have to be changed every three days.
Taipei Water Management Department Business Director Fan Huan-ying (范煥英) said the Feitsui Reservoir plays a key role in sending water from north to south with transfers to the Taoyuan Dayan Water Purification Plant which supports Hsinchu and the Hsinchu Science Park.
