There is an article in the paper today about a new transatlantic fibre cable. The article says that the location is secret because of the amount of traffic that it carries, I thought this was very unlikely so very quickly was able to find a leaflet giving the location. The same website has charts showing all the submarine cables around the UK.
The secrecy aspect is really little more than media hype, as it's not practical to keep this information away from the public domain.
The world's a busy place, and there are other projects and users of the sea that need to know where these are, to avoid them.
I've discarded the links now, but there was an episode a few weeks ago, when an undersea cable was snagged and the resultant loss of link stressed the handling of traffic to/from America. The traffic re-routed and service was restored without too much hassle. The owners aren't amateurs, and redundancy is built in, even if it can be stressed.
Now, if only they had the same detail on the old historic cables
I notice that they do list some of the redundant cables, I did wonder if some of the older ones were lifted for at least the part in inshore waters to avoid being snagged by fishing boats and other vessels?
I had a stab at trying to find the reports I mentioned, but even though they are only a few weeks old, failed miserably for some reason
But...
I did come across a related item with a little insight from 2006, with an interesting last line:
Quoted Text
I have worked in global telecom for a number of years, this does not surprise me at all. I have had outages caused by rebels on the Columbian-Ecuadorian border blowing up microwave towers, undersea cable cuts caused by earthquakes, etc. Undersea cables go out of service often near the cable landing sites, where it is shallower and the odds of human activity near the cables is much higher. Often times it is dredging operations, dragnet fishing, or cargo ships dragging their anchor on the seafloor that can damage an undersea cable enough to cause a shunt failure (power for the in-line amplifiers). Once it was speculated that the SEAMEWE3 cable was struck by a submarine, as the cuts on the cable were similar to that of a propeller striking it, and a submarine just happened to be photographed in port with damage to its screw and stern section at around the same time.
It can take the cable ship from several days up to a week to locate the break, then several more to complete splicing and service restoration. The "confidential-do not disclose" cable cut post-mortem reports make for an interesting read.
In 1968 the Alert laid a short cable in Scotland, starting just off Inverary, then down Loch Fyne to around Loch Gair, about 15 miles in all. While the cable could have been run as a landline, this would have involved digging up the A83 main trunk road, so it was quicker and less disruptive to run a submarine cable.
Dating from 1996, if you have some time to spare, you might want to work your way through 56 web pages worth of words on this subject:
Mother Earth Mother Board The hacker tourist ventures forth across the wide and wondrous meatspace of three continents, chronicling the laying of the longest wire on Earth.
Possibly more readable is the print version of the article.