Quality of Potable Water in Kuwait

Problem statement: Kuwait is an arid country with limited natural water resources. As such, Kuwait produces its drinking water using the Multi-Stage-Flash method (MSF) in distillation plants to produce distilled water from sea water. The distilled water is blended with the brackish groundwater in different blending ratios, to produce drinking water, as recommended by World Health Organization (WHO). Approach: The main purposes of this study were to determine the best blending ratios in the blending plants of Kuwait to get the best quality of drinking water according to the WHO guidelines and to reveal and control the corrosivity of the produced drinking water. In order to find out the best blending ratio, samples of drinking water from the different blending plants and groundwater samples from water well fields have been collected during 2007-2008 and analyzed for the determination of basic cations and anions. Moreover, water samples collected from the main pump stations were analyzed for Langelier Index, to reveal the corossivity level of the drinking water. Results: It was found that the best blending ratio between distilled water and brackish groundwater to obtain drinking water is in the range of 7-8% at Shuwaikh blending plant, 8-9% at Shuaiba blending plant and 8% at Doha blending plant respectively. While the best blending ratio at Az-Zour blending lines is between 3-4% and between 4-5% at Sabiya blending lines. Conclusion: It was found that the produced distilled water is corrosive and causing red water problem. In addition, it was found that the mean value of the Langelier Index at Shuaiba pump station is (-0.6) and the mean value of the total alkalinity is 21.4 mg L^-1 as CaCO₃, which reveals that the drinking water from Shuaiba plant is more corrosive than the drinking water from the other plants.