Environmental isotopes and hydrochemical investigation to evalute the seepage from Dwarege dam reservoir South Iraq (Missan Governorate)

Abstract

In the last few decades, a series of new Hydrological techniques have been developed to help in the assessment of leakage, Seepage and Recharge. The aim of this search is using the environmental isotopes (18O, 2H) combined with Physico-Chemical parameters (EC, Ca2+, Cl- , TDS etc.) have been employed to identify source of Seepage and Leakage pathways within Dwarege Reservoir-South Iraq. It’s the one of important reservoirs in the south of Iraq. In the present study, describes the relationship between the intake water and water dams. Using three types of water, (groundwater, Dwarege Reservoir and after reservoir). The results show that the stable isotopes composition of Groundwater from (-2.50) to ( -2.58%) for ä 18 O and from (–6.13) to ( -6.23%) for äD, respectively. The stable isotopes content of Dwarege reservoir in the studied area ranged from (-2.47%) and (-2.57%) for ä 18 O and from (-7.6%) to (-7.2%) for äD, while the water after Dam recorded (-1.38) for ä 18 O and (-2.27%) for äD, respectively. The hydrochemical facies of groundwater and Dwarege Dam is Ca-SO4 , while the hydrochemical facies of surface water after Dam is Na-Cl, due to the lithology of study area. Based on the result of isotopic values and hydrochemical facies there is interconnection between groundwater and surface water in the study area.