Urban farming or more pragmatically – bringing together agricultural and residential areas – is the most important mosaic piece.
An unconventional perspective of water management solutions for the Arabian Desert eco-region
Immediate savings, respectively import of Virtual Water.
80% savings of national water use, a massive Virtual Water pipeline.
Insecurity, dependency, injustice caused by land grabbing.
Size of fossil water aquifers that are used in North Africa and elsewhere.
Double use of desalinated water.
~100 m³ of water per capita and year.
Not as efficient as closing cycles in residences and greenhouses.
Size of population, same limits of initial desalination.
Access to the largest source of water on the planet.
Theoretically (long term) unlimited, practically limited by recharge of Gulf for sustainment of salinity*
No disadvantages for Energy required for groundwater, Gulf water inland/uphill transport has certain levels of toxins of water. from desalination units.
Table 1: Quality aspects of solutions that are already being realised The potential of the two Gulfs to provide water for biosaline agriculture (saltwater-based aquaculture) can be sustained through the withdrawal of hyper saline water from the most critical areas in the Gulf. This water must undergo full desalination by means of open-pond evaporation for example. Such procedure would have the effect of a natural outflow of the Gulf.
By Nicol-André Berdellé
audi Arabia and the UAE have distinguished themselves through implementation of solutions for water scarcity. While supply of natural water resources in the Arabian Desert is continuously running short, a few first remedies have been successfully implemented. These remedies are not immediately apparent or even visible, but can be gauged by the achievement of desert-greening in urban areas as well the well-sustained growth of population and industry. These remedies are namely outsourcing of agricultural production to other countries, reuse of wastewater for urban greening and shift to saltwater use for all sort of irrigation, agriculture included . However, these remedies also come at a high financial cost and critical disadvantages for the strategic development of the region.
Therefore, they can only be seen as a first generation of quick and limited solutions. The fundamental practice of seawater use through Reverse Osmosis (RO) is not considered here, because it is part of the basis for the regions’ existence and not new. Most notably, this option has already hit its natural limits and should by all means not be expanded any further. The loss of marine life and mangrove swamps in the Arabian Gulf cannot be part of a scenario which is acceptable. A dead body of water, stinking and loaded with waste, right at the shore, would reduce the living conditions in the area so much that it would have serious impact on the realestate market and the tourism industry. The use of fossil-water too is not considered because it is no solution in that sense, just an old practice.
Moreover, only few areas in Saudi Arabia still have sweet ground water including natural recharge (the three solutions highlighted here are sustainable). The outsourcing of the agricultural industry causes an immediate effect, but takes years to commence. The remedy of reuse causes an immediate savings effect but requires no implementation time at all. The shift to a saltwater-based agricultural industry takes decades. It started 40 years ago with the reintroduction of mangroves in Abu Dhabi. These areas cover about 11,000 hectares now and constitute a high-productive life-support system for the region. When salt-water based aquaculture or mariculture starts to grow in the area, these mangrove ecosystems will be in place to clean the nutrient-rich
wastewater from the growing number of mariculture facilities. This will also increase the mangroves growth rate. The amount of reused water from a million residents is sufficient for irrigation of 100km² of desert with fruit trees . This simple coefficient shows that the great vision of Sheikh Zayed can become a reality by continuation of the cleverly managed urban sprawl and incidental desert-greening done already. The quality of water from modern treatment facilities is so high that irrigation of food-crops is being recommended by experts and authorities. In several cities around the globe, like Singapore, water treatment is so advanced that wastewater is already reused as potable water. As a matter of fact, all cities downstream of one another use river water, partly coming from treatment plants, to retrieve fresh-
water for their local water grits. Once the vast desert-greening achievements with parks and other amenities are turned into food-producing greens, most problems of water and farming will be solved. Even in countries without water shortage, micro-farming and urban-farming are seen as the M-theory (theory of everything) of the food- and water crisis. Speaking of mosaic pieces of an overall water solution, urban farming or more pragmatically – bringing together agricultural and residential areas – is the most important mosaic piece. The experimental science of permaculture (advancement from the science of agro-ecology) describes such measures as ‘stacking functions’, a key strategy of nature for maintaining highly resource-efficient systems -integration. But this article intends to give a quick
overview of all significant water solutions. Although the remedies in place comprise a sufficient overall solution and have the potential to do so ultimately or on the long run, there will be progress. Better solutions with lesser disadvantages, less cost and higher efficiency will take their place.These next generation water solutions must include full desalination of seawater and brackish groundwater. Full desalination converts one m³ of saltwater into one m³ of freshwater, thereby avoiding brine discharge into the ecosystem of the Gulf. Full desalination also allows for inland operation, which is important to release the shoreline from the burden of the ugly and large industrial complexes: The coast must be reserved for salt-water based agriculture, aquaculture, tourism and the highproductive mangrove ecosystems .
MW & H2O Magazine Aug-Sep 2012