The entire basin was covered by the monitoring network, composed of the eight monitoring wells (with well depths ranging from 6 to 300 m), which were well designed for the monitoring project in 2013 by the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (Figure 3 and Table 1). The length of screen pipes in all monitoring wells varies from 1 to 10 m, and every monitoring well has only one screen pipe rather than multiple screens. The distance between the bottom of the screen pipe and the total well depth ranges from 0 to 3 m in the study area. Special attention was paid to monitoring the dynamic variation of groundwater level at different aquifer units and identifying the potential observation points affected by large-scale groundwater exploitation. All sites were equipped with a data logger (KADEC-MIZU II, Japan) and the groundwater levels were recorded at 30 min intervals from December 2013 to December 2014. In addition, a rain gauge was installed in the basin for the collection of precipitation data.