A U.S. professional repair vessel will travel to Tonga to repair the cables

According to the New Zealand stiff website reported on the 17th, the United States SubCom, one of the "big three" of submarine cables, is currently preparing to send a professional cable repair ship from Papua New Guinea to Tonga to repair the Tonga cable that caused the phone and Internet connection to be interrupted.

Cable Repair Ship Infographic (Source: Stuff)

Submarine cables in Tonga carry almost all of the communications in and out of Tonga, but stopped working shortly after the 15th eruption. After confirming that the 827-kilometer cable linking Tonga and Fiji was cut off at sea, phone and internet communications in and out of Tonga could be restricted for weeks. Samieuela Fonua, chairman of the Tonga Cable, said the international section of the cable had been cut off 37 kilometers from Tonga's capital, Nuku'alofa, and the domestic cable network connecting the main island of Tonga Tarbe and other islands was also cut off about 47 kilometers from Nuku'alofa.

He said that after communicating with the American cable company SubCom on the 17th, the Tonga Cable Company decided to start preparing to send SubCom's cable repair ship Reliance to Tonga, which may pass through Samoa. The vessel is currently docked in Port Moresby, Papua New Guinea, where Fonua said it could set sail in three to four days, when Tonga Cable may learn more about the repair plan.

Fonua said: "Due to volcanic activity, Tonga's siting conditions must be thoroughly assessed. These cables are very close to the volcano, especially our domestic lines. "Last year, the vessel underwent routine maintenance in Singapore and stopped in Papua New Guinea to get the crew vaccinated against COVID-19."

Courtney McDaniel, a spokesman for SubCom, said Reliance was "on standby for companies signing up for cable protection services" in the South Pacific.

The Tonga Cable Company cable was cut off in 2019 due to an anchor accident and Reliance was sent to repair it.

Reliance's base port is Noumea in New Caledonia. In that accident, the ship spent two weeks traveling to Tonga to find and repair the malfunction.

In the case that the cable is not available, some communication with Tonga can be carried out by satellite, but it is understood that these communications are affected by volcanic ash clouds.

Jamaican company Digicel Pacific operates a mobile phone network in Tonga and owns a minority stake in Tonga Cable. The company said on the 16th that it is "working to achieve satellite connectivity, which will provide services to limited customers of basic services and government departments", and the company's domestic mobile phone network across the main island of Tabu is running.

Repairing a major fiber optic cable break on land is usually a relatively simple task that requires only a skilled fiber optic connector worker to spend a few hours.

Accidental disconnection of cables is not uncommon during roadworks and other civil works, but repairing cables that have been cut on the seabed is more complex. It is often necessary to identify the approximate location of the fault from land by observing how far the light pulse travels along the cable before it bounces off. A professional cable repair boat will then head to the site and grab the cable with a submersible or deep-water hook, even splitting the cable in half if necessary in order to pull it onto the boat for repair.

Currently, dozens of specialized cable laying and repair vessels are stationed around the world, ready to respond to such emergencies.

Upstream News Compiled by Ruochen Yang