oa Artificial ground water recharge using treated wastewater effluents

Water-related problems are increasingly recognized as one of the most immediate and serious environmental threats to mankind. In particular, all the GCC countries being located in an arid region, suffer from lack of natural freshwater resources. Groundwater is the major source of water for irrigation in these countries. The groundwater aquifers contain either fresh or brackish waters. In countries like Kuwait and Qatar the groundwater available is mostly brackish. Agricultural development has put great pressure on groundwater resources and resulted in varying degrees of depletion and contamination as the demand for water has been increasing due to population growth and economic development. Over-pumping of groundwater has compounded water quality degradation caused by salts and other pollutants. In addition, saltwater intrusion is caused by over-abstraction of coastal aquifers. Meanwhile, the GCC countries are also facing changes in climatic conditions, such as rainfall patterns which affect the water cycle and limit natural groundwater recharge. The states of Kuwait and Qatar share almost similar problems and adopt the same approach in the management of their water resources under a severe stress of absence of natural freshwater resources. In these countries, wastewater collection serves almost all the population and tertiary wastewater treatment has been the common practice. Treated wastewater reuse is considered with proper attention to sanitation, public health and environmental protection. This paper will present a detailed evaluation of groundwater recharge using tertiary-treated or advanced (reverse osmosis) -treated wastewater. Recent advances, challenges, and future arrangements are discussed. A case study in Kuwait and an ongoing study in Qatar will be presented which includes advanced wastewater treatment comprising ultrafiltration and reverse osmosis systems, followed by the artificial recharge of the treated water into a groundwater lens. A simulation model is developed based on hydrogeological studies in which the augmentation of groundwater resources would provide water storage, and prevent depletion and deterioration of the groundwater. Hence, long-term sustainable groundwater management could be achieved.