Maritius Telecom T3 subsea cable in Amanzimtoti is expected to bring good news for people and marine life.
Businesses and consumers will benefit from enhanced capacity and reliability for services such as telecommuting, high-definition television broadcasting, video conferencing and advanced multimedia and mobile applications as Liquid Intelligent Technologies South Africa deployed the cable in the south of Durban on Monday.
The company will host and manage the submarine cable, while also providing the fibre landing facility that will house two subsea cables which will connect Mauritius to South Africa.
Liquid Intelligent Technologies is a business of Cassava Technologies, a pan-African technology group with a footprint that stretches over 20 countries, mainly in sub-Saharan Africa. It provides pan-African digital infrastructure with a fibre broadband network that covers more than 11 000km and lends its digital network to provide cloud and cyber-security solutions through partnerships on a global scale.
Dr David Glassom, academic leader in biodiversity and evolutionary biology at the University of KwaZulu-Natal, said the impact of such cables on marine life were considered to be low, and that this project was a viable one.
Glasson said the possible impact from a cable of this nature may arise from the surveys (usually acoustic surveys) to find the best route for the cable, from the actual laying of the cable.
“Changes to the marine life if a new habitat is provided, for example, a cable laid on an area of sand will allow organisms which need a hard surface to settle there or from the presence of the cable after it has been laid.”
Glassom said that none of these were presently considered high risk for marine life.
“The acoustic surveys are concerned only with the surface, or shallow subsurface of the cable route and so the volume and frequency of acoustic signals is a high frequency, low energy (compared to acoustic signals for mining or hydrocarbon exploration) and is considered to pose only a slight risk to marine mammals,” he said.
Glassom said that there had allegedly been cases of large mammals becoming entangled in the cables. However, new cables tend to be buried below the sand, and were less prone to coiling than earlier designs, resolving both of these problems.
“When cables are on the surface, there have also been instances of them being shifted by large animals, and this has the potential to cause a scouring effect on the seabed.
“Some animals, particularly sharks and rays, are extremely sensitive to electrical pulses; the pulses emitted by communication cabling (as opposed to power cables) diminish very quickly with distance from the cable, and are almost at background levels within a couple of metres away from the cable,” said Glassom.
He said that in aquaria, some behavioural changes had been seen in these animals in the presence of cables, however these had been slight and considered to cause major stress or ill health to animals.
SUNDAY TRIBUNE