The Rise of Underground Water in Kuwait
By Yacoub Yousef Al-Wazzan
Water in many parts of the world is the most limited and strategically vital resource, especially to countries with no natural resources of freshwater such as rivers and underground water. Natural resources of freshwater are one of the main human necessities. Kuwait has very limited sources of freshwater: sea water, ground water and treated waste water. Fresh water is mostly gained by utilization of sea water desalination technologies. On the other hand ground water, mostly brackish, is not a main component of Kuwait’s water resources. Ground water is also limited and essentially non-renewable. The Kuwaiti greenery master plan for nonresidential areas will not depend on using brackish water. Instead, the focus will be on using tertiary-treated wastewater. This paper will deal with the causes of the subsurface water rise problem in Kuwait, its effects and methods of treating this type of water for reuse purposes. (Al-Wazzan and Ebrahim 1, 37)
Subsurface water level rise is becoming a major problem in Kuwait, especially in residential areas. Water rise is causing surface water ponds, damaged roads, cracks in buildings, and flooded basements. The problem is mostly noticed during the start up of building a new building. Therefore, citizens are forced to extract this water and dump it into the rain pits which take it all the way to the sea. This process will put an additional cost and unnecessary delays before they can start putting the bases of their new building. Leakages from the piping networks of fresh, brackish and wastewater is one major cause of this problem. Excessive irrigation associated with the greenery program of Kuwait, in addition to the irrigation maid by the citizens to their gardens is another cause to this problem. The porosity of Kuwaiti soil also helped in making this problem even worse. More critical problems will rise as the population increases. (Al-Wazzan and Ebrahim 1, 37), (Ebrahim 315-316,324)
There are some methods in solving high level of subsurface water rise in Kuwait. One of the approaches is by planting deep rooting, water consuming trees. Another technique is by digging wells, extracting the water very carefully by not pumping sand with it. If this process is not done in a professional way land collapsing will occur. At the end and after extracting the water cautiously it is thrown as water waste. Since the quality of subsurface water is likely to prohibit any direct use due to its high salinity. Therefore, this water can be taken by extracting the water from wells, reducing/removing its salt content using reverse osmosis (RO) technology, and reusing it for greenery and other non human uses. (Al-Wazzan and Ebrahim 1, 37)
Based on a study conducted by Kuwait Institute for Scientific Research (KISR), RO is able to treat subsurface water by reducing/removing its salt contents by about 98%. Therefore, the best solution for solving the subsurface water level rise problem is by using the RO technology. (Al-Wazzan and Ebrahim 1, 37)
The principle of the natural osmosis; water flows (Fig. 3.1) out of pure water compartment and permeates through a semi permeable membrane into a concentrated salt solution. The membrane itself must have the Property to reject all kinds of dissolved salts almost completely, whereas it allows the water to permeate. The osmotic flux continues until a pressure imbalance (osmotic head) equal to the osmotic pressure is built up. At this osmotic equilibrium (Fig. 3.2), the net water flux through the membrane is zero. [The second principle is by the reverse osmosis,] applying a pressure to the salt water compartment higher than the osmotic pressure (Fig. 3.3) will force the water to flow from the salt solution into the pure water side and, hence, desalt the salt water. In addition, the direction of flow is changed and that is why this separation process is called Reverse Osmosis. (Abdel-Jawad 1, 9-11, 57)
Any RO system comprises transfer pumps, pretreatment system, high pressure pump, RO membranes, post treatment system, tanks for the treated water and drainage system for any unwanted water. To utilize a RO system, the subsurface water will be withdrawn from a well by using the transfer pumps and will be fed to the RO membranes after being pretreated and pressurized to a pressure higher than the osmotic pressure (Fig.3.4). The water fed to the RO system will produce two types of water. One with low saline water known as the product and the other is highly concentrated water known as the brine. The brine will be discharged to the drainage system, while the product will be post treated before reusing it for greenery and other uses. (Abdel-Jawad 1, 9-11, 57)
The RO is the simplest Desalination Technologies in Design, low in operational and construction cost, High Dependability in the Operation, low number of man power, operates at normal temperature and high water recovery. Although, the RO system seems perfect, it is not. The RO operates on high electricity, depends on water feed quality, the efficiency drops down due to biological effects and extra cost for membranes replacement.
Subsurface water rise in Kuwait is becoming a major problem, especially in residential areas that needs to be solved; otherwise, its effects will worsen. Some of the solutions are easy some are hard and others solve the problem with a great waste of water lose. However, using RO desalination technology can treat the subsurface water rising to the surface by lowering its salt content, and can be re-used for agriculture, landscaping and other domestic uses. (Ebrahim 315-316,324)
Adel-Mawad, Mahmoud. Sea water desalination by reverse osmosis. 1st. Kuwait: Kuwait foundation for the advancement of sciences, 1998.
Al-Wazzan, Y, and S. “Introduction.” A pilot study for the treatment and reuse of drainage of water in residential areas of Kuwait 1(2000): 1, 37.
Ebrahim, S, and Y. Al-Wazzan. “Pilot study on renovation of subsurface water using a reverse osmosis desalting system.” Desalination 3-6 October 2000: 315-316,324.
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