Some arid areas of Africa face severe water shortages due to minimal rainfall. An ancient system of drawing water from aquifers, the “qanat system”, could be helpful. Gaathier Mahed, an environmental scientist and groundwater management expert, said examined feasibility these systems. Tells us more._
How does the qanat system work?
There are reservoirs of water called aquifers underground, and a few of them may be found on the tops of valleys or near mountains. The qanat system draws water from these aquifers and uses underground tunnels to move the water using gravity for a lot of kilometers. The tunnel then exits right into a lower area.
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Once the water leaves the tunnel, farmers can use it to irrigate their crops. Water within the tunnel section will also be accessed via a well.
It is a system managed by everyone and its advantages are shared. Everyone has their very own interest and role to play. Social bonds may be strengthened – unlike the tensions we currently see over water resources.
Governance is a really complex municipal system. The laws governing the system have existed since ninth century. These regulations concern construction and proximity Tunnels in Kanata to one another. They also regulate exits from the qanats. For example, landowners at exits often is the first to use the water and must help manage it.
Where did it come from and where is it used?
Kanata were used through ages in arid and semi-arid parts of North Africa, the Middle East and Asia where water resources are limited. It is thought by various names: “foggara” in North Africa, “falaj” in Oman, and “qarez” in parts of Asia.
This is believed to have been the case developed in Persia in the primary millennium BC because the Islamic Empire proliferation within the Arabian Peninsula, the Middle East, North Africa and parts of Europe from 661 to 750 AD, as did the knowledge of qanat.
Currently, some qanat systems within the region, like those in Iran, are protected under cultural heritage status. Some of those qanats, although decreasing in number, are still used. They are largely protected for historical and cultural reasons.
Why is not it more widely used?
There are several the explanation why the tunnel system is just not more widely utilized in Africa.
Kanatas have to be built somewhere where there are suitable geological formations. Overall, they seem to be fractured sandstones. The groundwater level can also be necessary for the water flow within the qanat. The volume of water within the aquifer results from precipitation in mountainous regions.
Qanats can only be built where there may be a slope, resembling a mountain or valley. And it has to have a slope specific angle. If it is just too steep, the qanat will erode and it can collapse. If it is just not steep enough, the water won’t flow fast enough and will undergo chemical changes consequently of interactions with minerals within the soil.
Digging a tunnel and expanding the system over large areas is labor-intensive and might take a few years. Kanatas travel many kilometers and have to be maintained annually by removing accrued silt.
Knowledge concerning the construction of qanats and their maintenance is disappearing. People migrated from rural areas to cities and as an alternative adopted drilling in some areas.
Some qanats are drying up due to overexploitation of water resources.
Why should the system be used more widely?
In most cases, people in dry areas drill wells to access groundwater. These wells have a service life and eventually recent wells will need to be drilled. Pumps and materials don’t last ceaselessly, and wells can turn out to be clogged by microbes and fantastic material beneath the surface.
First of all, qanat is eco-friendly because it really works by gravity and doesn’t require electricity. It may even be used to generate clean energy. For example, in Iran, the cold air coming out of the tunnels in Kanata is cold used for cooling interiors of huge buildings.
Secondly, water losses due to evaporation are minimal compared to water surface supply.
Third, it might probably have a wide-scale impact. Kanatas are many kilometers long and once water reaches the flood plain it might probably achieve this water repeatedly hectares of land.
Fourth, it promotes social cohesion. Many individuals with different skills are involved in maintaining the system.
Fifth, system life goes beyond deep well, i.e. only about 20 years. Tunnels don’t clog as easily as wells.
Finally, the standard of water coming from the mountains is significantly better than water within the plains. It will probably be less salty and higher for crops and folks.