One in four people on Earth face shortages of water for drinking, sanitation, agriculture and economic development. Water scarcity is expected to intensify in regions like the Middle East and North Africa region, which has 6% of the global population but only 1% of the world’s freshwater resources. A book, Unconventional Water Resources, based on the most up to date information, identifies eight broad categories of unconventional water sources. Fog harvesting is already happening in parts of the world. Remote communities in Chile, Morocco and South Africa have used vertical mesh nets to harvest fog for over 100 years. Viable sites are typically open locations with a fairly high elevation, exposed to wind flow. Desalination – removing salt from seawater – contributes over 100 million cubic metres of water a day, supporting about 5% of the world’s population. Almost half (48%) of the global desalination capacity is located in the Middle East and North Africa region. Advanced treatment systems can convert wastewater into potable water. Treated wastewater provides 25% of the potable water supply of Windhoek, Namibia’s capital, for example. And finally, A financial feasibility analysis of towing icebergs to Cape Town, South Africa suggests it is an economically attractive option if the icebergs to be towed are big enough: at least 125 million tons. Wrapping icebergs in a net and then a mega-bag would likely prevent breakup and reduce melting, studies suggest.
SOURCE: THE CONVERSATION