Effects of groundwater on desalinization in coastal reservoir and adjacent aquifer

Coastal reservoir provides the additional storage capacity of freshwater in coastal zone which greatly alleviate the water shortage in stressed areas, and the salinization of reservoir water degrade the utility of coastal reservoir. Salinization may result from inadequate desalinization in early operation stage, and groundwater as the important source of freshwater to coastal reservoir and adjacent aquifer was obviously have significant impacts on salinization which was in a dearth research. Laboratory experiments and mathematical model were designed to further discuss the influence of groundwater on the desalinization. The results from experiments shown that with the groundwater discharge rate increased, residual saltwater distribution result from intruded fresh groundwater was further moderated. Coastal reservoirs also greatly changed groundwater discharge pathways to sea. Without coastal reservoir, groundwater discharge to sea directly, while with coastal reservoir, part of groundwater would firstly discharge to coastal reservoir, desalinate the reservoir water, and then to sea. Mathematical model was designed for the prediction of the salinity of reservoir water, and the results from model could indicate the accuracy groundwater discharge pathways in coastal reservoir and adjacent aquifer. These results demonstrate the complexity of the groundwater system in adjacent aquifer of coastal reservoir, and may have great implications for future investigations on the predication of water quality during the full operational period.