On the edge of the Sahara in southern Morocco, where an average of five inches of rain falls per year, scientists have tapped an unlikely and precious source of clean drinking water: fog.
Using vast vertical mesh nets, suspended on the slopes of Mount Boutmezguida, the rural community extracts moisture and water particles from blankets of dense fog, condensing them into a receptacle. A network of pipes takes some 6,300 litres of harvested freshwater daily to the villages below.
It’s an effective system — aptly dubbed cloud fishing or cloud seeding — that leverages familiar scientific principals with modern technology to help bring clean drinking water to one of the driest places on earth.
And it’s not the only innovative idea to help address the world’s fast growing freshwater needs, says a Hamilton-based think-tank.
A new book from United Nations University Institute for Water, Environment and Health (UNU-INWEH) lays out how unconventional water resources, from deep underground aquifers to icebergs in the Arctic, can curb the mounting global shortage.
“These unconventional resources are a response to the limitation of conventional water sources, like snowmelt and river runoffs, which are becoming less sufficient,” said Mazoor Qadir, deputy director at the institute and lead editor of the book called “Unconventional Water Resources.”
Qadir said almost half of the countries in the world are expected to experience water scarcity by 2050, and conventional water resources aren’t expected to cope with burgeoning demands, particularly in arid areas.
That makes the need to tap into vastly underused unconventional water resources all the more pressing.
“Unconventional Water Resources,” released in May, lays out the vast potential of different types of unlikely water supplies.
“The time is right now,” he said, adding harnessing the potential of unconventional resources could benefit “billions of people.”
Some such resources are in places you wouldn’t imagine.
At shallow depths of the world’s continental shelves, for example, there are untouched aquifers created millions of years ago that contain vast quantities of water — as many as 500,000 cubic kilometres’ worth, the book notes. Just one cubic kilometre of water equals the volume of 400,000 Olympic swimming pools.
Consider, too, transport ships. All ships in the world of 400 gross tonnage or more are required to have on-board treatment options to desalinate (converting saltwater to freshwater) the ballast water that keeps them from capsizing. When refined, this potable water could be sold to port cities in acutely dry regions, the book suggests.
Other resources highlighted in the book include micro-scale capturing of rain that would otherwise evaporate, reusing municipal wastewater and catching some of the billions of tons of freshwater melted from icebergs.
They stand as creative solutions that could help many of the one in four people in the world who suffer from shortages of water for drinking, sanitation, agriculture and economic development, said Qadir.
The institute’s book — produced over three years in collaboration with the UN’s Food and Agriculture Organization and the UN University’s Institute for Integrated Management of Material Fluxes and Of Resources — was released May 26.