Subsea Cables & Internet Infrastructure

The map shows the ultimate challenge for any cable crossing the North Pole. The Bering Strait is the exit for any polar project trying to reach Asia. But the average depth is only 30 to 50 meters. As you learned in school, the Bering Strait was a land bridge during the last Ice Age lasting from 37,500 to 12,000 years ago. The lower the temperature, the more water vapor is deposited as snow and ice on land. Hence the oceans recede as temperatures fall.  The construction rule of thumb is to bury a submarine cable when the sea is a thousand meters or less deep. This means a polar cable must be buried for over two thousand kilometers as the map shows. The North Alaskan coastal Quintillion cable's burial depth varies between two and four meters with a maximum of 12 meters. Deep burial is intended to protect the cable from icebergs scraping the sea floor in shallow water. A dual cable design raises per meter cost because the protect path would traverse the more shallow Russian side of t...

Quintillion was really formed to build a subsea cable from Japan to Europe via the North Pole. It acquired the assets, mostly human capital and preliminary research, of Arctic Fiber in 2016, and as a first step deployed a North Alaskan subsea cable serving coastal communities plus some terrestrial fibre. See the map below on the left.  No expense was spared protecting it from the harsh environment. Quintillion was buried 3.5 to 4.5 meters deep, probably a record, and for landings a bore pipe was deployed. Nonetheless, it was an ultra-high risk project. Icebergs gouge the sea floor as they float. It is called ice scouring. They carve trenches as deep as 15 meters into the sea floor. The fact is that there is no viable protection against them. Moreover, there were no icebreaker cable ships to fix the cable in case of outages. This meant that outages during autumn, winter or spring could not be fixed until late summer. As an example, Quintillion's most recent outage began in January 2...

The three fibre pair Quintillion cable went live in 2017. Its current throughput is 10 Tbps per fibre pair. It includes terrestrial back haul from Prudhoe Bay down to Fairbank, Alaska, in the middle of the state. The cable was deeply buried with an average depth of 3.7 meters with bore pipes used to bring the fibre pair ashore to the manhole. Each landing threads the fibre optic cable through steel conduit at least 18 meters under the sea floor up to 1.6 kilometers offshore. This was accomplished via horizontal directional drilling. Project cost was around $150 million. The cable is a godsend for these Alaskan communities and was built to top notch engineering standards. But it still suffers from ice scouring incidents where icebergs cut through the sea floor and have severed or severely damaged the cable. A major outage occurs roughly once a year, but the real problem is the repair time. It is simply not economical for a subsea cable to own an icebreaker or to risk a cable ship's ...

Nordunet's cost estimates are way off base. It is not a 200 million Euro project, but a half billion Euro project. It would require a special cable ship designed for Arctic climates together with two icebreakers to be on the safe side. The proposed paths are as long as many non-Arctic cables whose construction costs were in the $200 million to $300 million range. But those projects did not require specially designed cable ships nor icebreakers for deployment or for the necessary geophysical survey undertaken before construction. The cable would probably be double armoured and the design phase costs alone probably twice the norm.  So it is a given that upfront costs will be extraordinarily high. And here is the dagger in the heart: ice scouring. Floating glaciers scrape the bottom of the sea floor in the Arctic coastal areas. One or two meter burial won't be enough for the Northwest passage route raising the cost. But going deeper for burial may require special equipment or not...