Regional groundwater flow modeling in Zhangye Basin a of Heihe river watershed, China

Groundwater in Zhangye Basin accounts for a large amount of quantities during supplying water for Zhangye City. In order to find out the optimal groundwater development plan to achieve the sustainable development, a regional groundwater flow model was constructed for the study area. Hydrogeological parameters were calibrated against observed groundwater level hydrographs and flow field. Then, the model was used to analyze the flow system and the trend of groundwater levels changes. The modeling results show that total recharge was 1216×10⁶ m³/a and total discharge was 1365×10⁶ m³/a for the modeling period, i.e. 149 M m³/a of groundwater storage was over drafted. Ten year predictions show that groundwater level would continuously decline in the area under current groundwater exploitation schemes.