You may not know it, but a lot of how we live is reliant on subsea cables. From power cables to cables that connect the world to the internet, they’re buried deep under our seas and oceans, silently working to improve the way we live and work — but how did they get there?

Given the location and nature of the work undertaken, laying subsea cables is a difficult, laborious and dangerous activity, as subsea cable laying company Fraser Hydraulics explains. In order to ensure the success of the operation and the safety of workers, specialist equipment is required.

Each of the cables is specially constructed to operate under harsh conditions and high pressure. The cable is then loaded onto a modified ship, each capable of carrying up to 2,000km of cable in length. It is stored coiled in a specially created hold and can take up to a month to coil in preparation for storage.

At the start of the laying process, a long section of cable is attached to the landing station. The other end is carried out a few miles in the sea and attached to the cable on the ship. The ship can then start the laying process, whereby following the cable operator’s plans, the cable is slowly laid out on the seabed.

To avoid damage to the cable, it’s important that it isn’t left to sit atop of the seabed, where damage is likely to occur. To ensure the cables are firmly embedded into the ocean floor, a plough is used. As the cable is laid out, it is fed through the plough which is used to carve out a trench in which the cable can lie.

Maintenance of subsea cables is essential — usually taking place every ten years — yet difficult. In this instance, specialists will rely on submersible cameras and lights to identify what the issue is and where it lies, as well as advanced tools like robotic arms to carry out the necessary repairs.

Each project is unique, so the process will alter accordingly. Nevertheless, despite its complexity, laying subsea cables is a crucial process and, in our growing digital world, one that helps us live interconnected lives.