Groundwater Recharge from Dams in United Arab Emirates

This study presents a comprehensive analysis of the groundwater recharge in the dams of the northern region of UAE. The study area included dams at Wadi Al Bih, Wadi Tawiyean, and Wadi Ham. A modular three-dimensional. MODFLOW was calibrated and validated to simulate the groundwater flow and recharge from rainfall events. Apart from the ponding area, the recharge coefficient is in the order of 0.2. The recharge efficiency of Wadi Ham dam calculated as the ratio between the total recharge from the ponding area and the total storage during a specified period is around 47%. The remaining 53% of the water storage is mostly held in the unsaturated zone and some amounts are lost to the atmosphere through evaporation. The recharge efficiency of Al Bih dam is around 31.4%. The major part of the infiltrated water is stored in the unsaturated zone causing a significant increase in the soil moisture content including the loss to the atmosphere through evaporation from the ponding area. The efficiency of Tawiyean dam is around 22%.