Coupled Simulation And Predict Model For Surface River And Groundwater In Jining City, China

With the boom of population, the expansion of city and the rapid development of industry and agriculture, water demand is increasing accordingly. In some areas, a series of geo-environmental problems due to groundwater over pumping, such as land subsidence, deep groundwater contamination and so on, have occurred. Thus, in order to realize the reasonable exploitation and utilization of regional water resources and then the sustainable development of social economy, the conjunctive use of surface water and groundwater is essential. The coupled modeling and sound dispatch of surface water and groundwater are an effective measure to realize the sustainable development of regional water resources.In this paper, coupled numerical model of river water and groundwater is established according to hydrological and geological conditions and the analysis of hydraulic mechanism of river-aquifer interaction. Based on the Saint-Venant equations, the river flow model is simulated by the chase method derived by the use of Preissmann Weighted Implicit four-point scheme. Groundwater flow model is solved with finite difference method by the software Visual MODFLOW. And the models are coupled by the exchange of water. The parameters in the model are calibrated by the comparison of the calculated water level and the measured water level of the observation wells. Because of the long-term over pumping of groundwater in Jining city zone, the aquifer there is in negative balance condition. Combined with the South-to-North Water Transfer East Route Project, the surface water is diverted from the Great Canal near Houying hydrologic station to Jining city zone to control the exploitation of groundwater for the environmental protection. The water demand in future years is predicted by model of water demand prediction; precipitation and river level at hydrologic station are predicted by autoregressive model. The water diversions in different scenarios from the Great Canal to Jining city zone are obtained according to the change of aquifer water storage calculated by the Zone Budget module of the software Visual MODFLOW.