The Martlet

It can sometimes be frustrating to set up a home entertainment centre, computer or satellite dish. Projects like these involve numerous electronic components that need to work properly and be set up correctly, or else the whole system will not work.

So imagine how hard it would be to deal with electronic equipment set up at the bottom of the ocean.

That’s exactly what the people working at NEPTUNE Canada had to face when one of the components of their undersea network broke down a few months ago.

NEPTUNE Canada is a massive high-tech underwater observation network located off Vancouver Island’s west coast, designed for a wide range of purposes including monitoring tectonic plate movements, observing marine ecosystems and tsunami research.

But back in September, its network was damaged and completely shut down. NEPTUNE technicians had to determine where, exactly, in the vast 800-kilometre loop of fibre-optic and power cable along the ocean floor, the damaged part of their network might be.

According to NEPTUNE director Kate Moran, there are a lot of things that can damage an underwater cable system, including trawler ships and underwater landslides. Luckily, the technicians were able to quickly pinpoint the source of the trouble.

“With fibre optics, you can ‘ping’ the cable from both directions to locate where the failure is, so we had narrowed it down to what we thought was a branching unit at [Folger Passage, near the entrance to Barkley Sound],” explains Moran.

Moran says within 24 hours, NEPTUNE was able to restore power and network connections to the other nodes in its undersea network, which begins and ends at its shore station in Port Alberni.

“Because this is a loop system, it provides redundancies so you get power from Port Alberni, and you can go in one direction or the other — power and data,” says Moran.

While NEPTUNE’s network was mostly up and running again, actually repairing the faulty component proved to be a much bigger challenge.

The first hassle was waiting for the availability of a cable repair ship, the C.S. Global Sentinel, which is collectively contracted by various telecommunications companies running underwater cables in the Pacific Ocean.

By early November, it was NEPTUNE’s turn to get the ship. But then came the second hassle — stormy weather and strong ocean currents.

“Currents there are really high, and the weather was really bad, so they had to stop operations for at least three days,” says Moran. “They went into the inlet and hid. It’s a big ship, but they couldn’t stay out there.”

During the brief period of time when the Sentinel was able to do repair work for NEPTUNE, the office table–sized branching unit was pulled out of the ocean for detailed work done by technicians onboard the vessel. Other repair work was done by a remote-controlled underwater vehicle.

“The one we use for installing instruments is extremely precise,” says Moran. “We have very fine controls on the manipulator arm.”

Beyond fixing the damaged component, another tricky aspect to these kinds of underwater repairs is the cable system.

“When they cut the cable, they can’t just leave it on the sea floor,” explains Moran. “So they have these huge buoys where they install the cable they’ve just cut, and leave it there, hanging in the water column so it stays in relatively the same location. There’s a lot of heavy lifting, and being able to put things back in the right place.”

Stormy weather meant repairs to NEPTUNE’s branching unit at Folger Passage were not able to be fully completed, so final repairs and inspection have been postponed until summer 2012.

While the cost of the repair came at a million-dollar price tag, it was covered under NEPTUNE’s budget. Moran explains that underwater cable damage is relatively common in the telecommunications industry, so some kind of disruption to the Neptune’s network was expected.

“We call it known unknowns,” explains Moran. “We know they’re going to happen, but we don’t know when.“