The potential of using beach wells for reverse osmosis desalination in Qatar

Abstract

Qatar is an arid country, with limited water resources. The country relies on desalination of seawater to meet the increasing water demand for municipal and industrial needs, while the agricultural sector uses the precious fresh groundwater. Groundwater underneath Qatar is mostly saline or brackish with small lenses of fresh water in the northern part of the country. Brackish groundwater in Qatar has a Total Dissolved Solids of less than 10,000 mg/l, compared to seawater, which is 35,000 mg/l. Using brackish and saline groundwater for desalination via beach wells is less costly and more environmental friendly than direct sea water intake, which is being used in Qatar. The main challenge facing beach wells usage is their questionable capacity to provide enough quantities for desalination plants. This study investigates the optimal location and the maximum yield of beach wells in Qatar, using Sea Water Intrusion model (SWI2), coupled with MODFLOW. Model results show the maximum yield of wells at a depth of 100 m is 16,000 m3 per km2. This quantity is good enough for a medium size reverse osmosis plant. Based on hydrogeological settings, the proposed location for the beach wells is near Al-Khor town and to the north of it.