The Channel Tunnel

It is also the longest undersea tunnel in the world, the undersea section being 37 kilometres long. For hundreds of years the building of a link between France and England was thought to be impossible. No-one thought it could be done. The Channel Tunnel was eventually started in 1987 but frequent problems nearly caused the project to be abandoned. Some people thought that the Channel Tunnel project was impossible even while it was being dug.Physical difficulties encountered were so severe that the completion of the Channel Tunnel was brought into question many times. Wet ground, safety problems and fire risks were only some of the problems that were encountered.

The unexpected wet ground caused multiple and severe problems during the building.

The ground had been surveyed before the drilling and the ground was said to be relatively dry. “Ground that had been widely predicted as being a tunneller’s dream was in reality a nightmare.” (Byrd, P. 76) In March 1988 the TBM (Tunnel Boring Machine) on the English side hit weak rock and water poured in around the TBM and workers. (Fine, P. 31) While the TBM was drilling, rocks fell around and behind the TBM putting lives at risk. (Fine, P. 31) A metal cover was designed for the TBM to shield the workers behind the TBM and protect them from falling rocks. The concrete slabs could also not be placed properly because of the wet ground. This was because the wet ground loosened the tunnel walls and rocks fell off them. The outer shell of the tunnel then lost some of its surface area and the concrete slabs could not be properly placed and could fall down. This meant that they had to use different methods to place the concrete slabs in that area. With bad and wet ground the locomotives, which were electric and battery powered, weren’t running properly. “In the wet, the wheels of the locos lost traction ands span on the slopes.” (Byrd, P. 80) They also couldn’t recharge. Without their batteries to power them, the locomotives couldn’t get to certain areas. They also couldn’t bring supplies to the workers and get rid of the debris. The locos were redesigned to cope with the new problems by increasing the weight for better traction, getting larger capacity batteries, the pantographs were changed and the power of the engines was increased by almost 30%. “Cost was a problem, but so was time.”(Byrd, P. 80) This was a large problem because there were over 100 locomotives in the operation that needed to be modified. After upgrading ventilation they were given permission to use diesel engines which were less likely to have a power failure. This work had never been done on this scale before and the problems that kept popping up were new to everyone so they had to think up new ways to deal with them. There was also a problem with time and cost and all that made the wet ground life-threatening to the project.