CAPE TOWN - Harvesting icebergs could help provide for at least 20% of Cape Town’s water needs, a marine salvage expert said on Wednesday.
Offering solutions to Cape Town’s water woes while addressing delegates at the African Utility Week in the Cape Town convention centre, Nick Sloane said the answer to Cape Town's water needs may just be in “mother nature’s icebergs”.
During a keynote session, where solutions from nature were explored to address increasing energy and water constraints, he told delegates that a total of 140,000 icebergs were drifting in the southern oceans and melting.
“It sounds like a crazy idea but if we break it down, it is not so crazy after all,” he said.
His address followed director of water and sanitation in the City of Cape Town, Peter Flower’s who also presented on the water crisis in the city.
Flower told delegates the city still needed to reduce consumption to 450 million litres of water per day to keep Day Zero at bay. With the current usage at 500 million litres per day, the situation would remain dire despite measures employed by the city to reduce consumption.
According to Sloane, icebergs break off in Antarctica and hold some of the purest quality water that is between 15,000 and 20,000 years old.
“About 2000 million tons of ice are breaking off every year,” he said.
The idea is to use the current system to guide these icebergs towards the Cape.
“So, they are coming our way, we just need to know how to deal with it.”
He further said that the iceberg could be captured in the area round Gough island and would ultimately have to be guided and moored about 40 km offshore from St Helena island to be harvested.
He added that they would then have to “create a saucer to capture the melting water that could deliver up to 60 million litres per day”. With milling this volume can increase to 150 million litres a day that is then pumped into tankers and ferried to land where it would be treated before it went into the water system.
“So, with four to six of these tankers, 150 million litres can harvested per day for one year.”
According to Sloane this is something that can be viable. “Can it be achieved? Well we are looking into it.”
Director of BiomimicrySA, Claire Janisch also shared case studies on how nature’s “wisdom can be copied” to help with the increasing pressure on and challenges with natural resources.
“Solutions to our problems already exist in nature,” she said. “We can improve our physical world by following nature’s example. One such an example is emulating the humpback whale’s attack manoeuvre in wind turbines to increase efficiency and learning about desalination through the example of the mangrove trees that use sea water to survive.”