By Kathrin Hille in Taipei

In 1850, a ship called Goliath laid the first submarine telegraph cable
linking Britain and France. The cable, which consisted of a single wire
insulated with rubber, failed a few hours after reaching France – a French
fisherman had hauled it in with his catch and to free it had to cut the
cable.
Nowadays submarine cables, mostly using fibre-optic technology, link all the world’s continents except Antarctica in a sophisticated global
telecommunications system used by billions.
But on December 27, international phone lines and internet connections
across most of Asia almost collapsed when an earthquake measuring 6.7 on the Richter scale hit off Taiwan’s southern coast.
Telecoms companies say services are back to normal, but users in the region and in Europe trying to call Asia are still experiencing bad lines and
difficulty in making connections.
Global Marine, a private UK company specialising in laying and repairing
undersea cables and which traces its origins back to the 1850 operation, has three ships in the Bashi Channel between Taiwan and the Philippines where it is working on three of the 21 cable faults that the quake caused.
Ian Douglas, Global Marine Asia director, says the bulk of the affected
infrastructure lies at such great depths and in such a challenging
environment that the company has had to resort to old-fashioned techniques.
“Normally we would use unmanned submarines to bring the cables up to our ship and repair them there, but these remotely controlled vehicles can only go down to 2,000 to 2,500 metres,” he said. “The cables we’re dealing with here lie up to 4,000 metres deep.”
So the repair ships are using a traditional technique instead: they sail
back and forth across what they estimate is the cable’s path and try to pick it up with a grapnel hook.
“It’s a jungle down there,” says Mr Douglas.
The cable systems connecting Asian countries with each other and the outside world are large loops that all pass through the Bashi Channel, the
best-placed strait connecting north-east and south-east Asia.
The high concentration of undersea cables means once one cable is picked up, it might drag others with it. The crews seek to cut the cable and attach its two ends to buoys before making the repairs and linking the two ends again.
But the Bashi Channel has some of the strongest currents in the world, and the crews work in winds of up to 30-40 knots.
“We need to use special buoys that will not just be swept away and vanish,” says Mr Douglas.
Moreover, many cables that run east-west were buried under the seabed in the quake.
Although the telecoms companies know the original path of their cables and can determine with lasers where they are broken, the crews on the ships cannot see what the seabed looks like, so progress is hard to predict.
Global Marine’s work has been delayed because it needed to fly in new
equipment for a cable between south China and Taiwan.
If everything goes smoothly, this repair will be finished next week and the
other two faults the company is working on are scheduled to be repaired by the end of the month.

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