It was proposed 70 years ago by a maverick California scientist at Scripps.
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A year ago, Cape Town, South Africa was suffering one of the worst droughts in its history. The city of 4 million made headlines by being one of the first major cities on the planet to run out of municipal water, and entering a so-called Zero-Day status that seemed a harbinger of things to come for many other cities (Los Angeles included) facing dire water shortages.
Cape Town averted disaster by orchestrating a series of conservation and water diversion measures that helped in the short term. However, the water supply situation is still tenuous, and many people believe that similar Zero-Day scenarios could become a part of the new normal, an era when drastic, some might say crazy solutions enter the realm of the possible.
Enter the Antarctic iceberg idea. Bloomberg has a wonderful story this week about Nicholas Sloane, a 56-year-old South African marine-salvage expert who is developing a plan to tow an iceberg from Antarctica to the South African city, where it would be moored off-shore and hacked and “mined” for fresh water.
One problem with the idea is that to make any dent in a large city’s water supply, the iceberg will have to be big. Very big.
“To make it economically feasible,” Sloane tells Bloomberg. the iceberg would measure about 1,000 meters (3,281 feet) long, 500 meters wide, and 250 meters deep, and weigh 125 million tons. “That would supply about 20% of Cape Town’s water needs for a year.”
As outlandish as the idea seems, some scientists think it’s possible, or at least worth a try. Sloane’s company Iceberg Towing International has hired some of the most reputable names in iceberg transport (not a long list), and feasibility studies are underway.

But one interesting footnote to all of this is that the idea of towing icebergs is not new. In fact, one of the early proponents of towing icebergs was an iconoclastic ocean scientist from the Scripps Oceanographic Institute in San Diego. In the late 1940s, John Isaacs proposed transporting an 8 billion-ton iceberg to San Diego to relieve California droughts.
The idea was to capture “an eight-billion ton iceberg, 20 miles long, 3000 feet wide, and 1000 feet deep in the Antarctic and towing it up to San Clemente Island off San Diego in a matter of 200 days.” That’s thinking outside the box.
Speaking of a box, one of the interesting details of the story is how much better Antarctic icebergs are for this kind of thing than those in the Arctic. Arctic icebergs are the pinnacled, mountainous type that we are most familiar with from photos, and the kind that likely sunk the Titanic. Antarctic icebergs are “tabular”, big and flat, not soaring blue spires like those from Greenland. This makes them far easier to transport and less likely to fall to pieces while being pulled across vast ocean distances.

By most accounts, Isaacs was an odd, but brilliant character. He was also a well-known polymath who became a world-renowned scientist, engineer, teacher, naturalist, fisherman, author, inventor, and Scripps professor. His colleagues called him a “giant of science” and an “idea man”, willing to take on most any problem that interested him with implacable energy and often unorthodox solutions. Over the course of his career, he was elected to the American Geophysical Union, the National Academy of Sciences, the National Academy of Engineering, and the American Academy of Arts and Sciences.
After he died, the iceberg towing idea came up several additional times, including a wonderful 1973 Rand study titled “Antarctic Icebergs as a Global Fresh Water Source” that proposed creating an “iceberg train”, essentially a series of icebergs tied together like boxcars. In the paper, RAND gave a nod to Isaacs idea and tried to flesh out the details of how such a scheme would actually work.
As recent as 1978, California’s legislature endorsed the idea of towing two icebergs to southern California for drought relief.
Isaacs died in 1980. Needless to say, in the age of climate change, it would be nice to have a man like him around again. However, his legacy does live on: Through the California Sea Grant program Scripps awards six Undergraduate Research Assistantships each summer.
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