Qatar has one of the fastest growing economies in the world. Revenues from the mid 20th century discovery of oil are primarily responsible for its recent economic growth. Qatar has experienced a population expansion from approximately 11,000 in 1940 to over 1.9 million in 2013 and continues to grow rapidly. Water is remarkably scarce in this arid desert country that imports 93% of its food, yet paradoxically, Qatar maintains one of the highest per capita water consumption rates in the world. There is no surface freshwater, and a majority of the shallow aquifers that once supported Qatar prior to its oil induced population expansion are long since depleted and salinized.
The import of food is of supreme priority, yet secondary in nature to the importance of local access to immediately available physical fresh water. Qatar’s regional carrying capacity has long since bypassed its critical threshold and can no longer sufficiently sustain its expanding population. Revolutionary water harvesting methods are of extreme importance to support this expanding population.
Fresh water production from the fossil fuel driven desalination of seawater has been used as an innovation to remedy physical freshwater scarcity in Qatar. Desalination extracts salt, minerals and contaminants found in seawater by methods of distillation, reverse osmosis and electrodialysis. In the method of distillation, water is heated to a vapor, leaving unwanted molecules behind, and condensation converts the vapor back into a purified liquid. Instead of heat, reverse osmosis uses pressure; water molecules are forced through a special membrane under pressure leaving salt, minerals and contaminants behind. Electrodialysis utilizes the polar properties of seawater to separate unwanted molecules through ion specific membranes.
There are however, many complications concerning this method’s continuity with sustainable longevity. Although Qatar requires a comparatively urgent demand for desalination, the global demand paints a much larger picture. Collectively the world desalinates billions of gallons of water each day. About 4.5 cubic meters of seawater are used to produce just one cubic meter of desalinated water, creating an amazingly substantial volume of water manipulated globally by humans each day. Fueled by expensive crude oil or gas, desalination is an energy intensive process that discharges considerable magnitudes of pollutants. Desalination also discharges brine, the remaining concentrated salt water after fresh water extraction. High concentrations of salt water seen in brine are discharged back into the environment posing complications with species biodiversity. Although fossil fuel driven desalination of seawater increases regional self-sufficiency, its operation requires the utilization of finite natural resources. Supplementing further population growth with unsustainable desalination methods puts ensuing generations in grave danger when the finite resources used to administrate this method are exhausted. Many world leaders in fossil-fueled desalination deny impediments with its sustainable longevity, and their competing interests are apparent.
For an example of a sustainable solution to counteract the negative impacts of fossil fueled desalination, check out the frenchwellness article on Seawater Greenhouses.