Internet speeds in the Channel Islands have slowed considerably after a ship dropped its anchor over a busy submarine cable lane.

It is not known why the ship, thought to be the King Arthur, lowered its anchor in what could be restricted waters, but the results have been clear - several cables cut, with communications rerouted via France.

A cut below the rest

Jersey States-owned telecom company JT said in a statement: “JT expects some disruption to services over the next week or so after three out of its four international submarine cables were cut yesterday evening. It is thought that the three fibre-optic cables to the UK were cut by a ship dragging its anchor along the seabed, which also cut a number of other submarine cables in its path.

“All communications traffic to/from the Channel Islands is now being routed via the submarine cable link with France instead – but with all traffic now using this connection, customers may notice some impact on services. JT engineers have been working on the situation throughout the night, and have already mobilize the specialist team that repairs major undersea cables. It is not possible to get a precise time yet on when those cables will be repaired, but the work will be completed as soon as possible.”

Back in January, a JT cable was cut by a ship that dropped anchor in stormy weather. The single cable took a week to repair using a specialist ship, with 800m (2,500ft) cut out using remote controlled underwater equipment.

Daragh McDermott, JT’s director of corporate affairs, said: “We would like to sincerely apologize to our customers for any disruption to their services.

“We are working as quickly as we can to get our undersea cables repaired, and normal service resumed, and will keep customers up-to-date with what is an extremely challenging emergency engineering operation at sea.

“It is exceptionally unlucky and unprecedented for three submarine cables to the UK to be cut in the same day, and it proves the value of having multiple links in the network, in order to provide a back-up connection via France.

“There are lots of cables running across the seabed, and we understand that it is not just JT who have been affected in this way, with other cables also having been cut.”

Guernsey’s largest telecom company Sure said that its voice cables were cut, but that it has been working with JT to reroute its data through the rest of the Sure network.

Jersey Treasury Minister Senator Alan Maclean, told the BBC: “If there is damage attributable to a particular owner then I’m sure they will pursue it.”

For more on submarine cables, their history, and their future, be sure to check out our latest feature on the industry from our October magazine.