Analysis of Groundwater Overexploitation Based on Groundwater Regime Information

Although groundwater overexploitation is a global problem, there are no unified standards for its identification and determination. To date, groundwater overexploitation has mainly been evaluated using the groundwater quantity balance and effect of groundwater exploitation on the environment. However, it is difficult to determine groundwater exploitation for an agricultural irrigation area owing to the lack of detailed environmental monitoring data. We used the experience of previous studies to introduce a novel identification model for groundwater overexploitation by relying on groundwater regime information and multi-factor analysis. The model was applied to the Songhua River-Naoli River area, Sanjiang Plain (China). In the demonstrated model, the study area was divided in the context of the risk of overexploitation into natural and non-natural regime areas according to groundwater regime characteristics. The areas were identified by analyzing groundwater flow fields, cones of groundwater depression, and storage variation. The analysis demonstrated that the study area could be divided into high-risk, medium-risk, low-risk, and non-overexploitation areas with corresponding area ratios of 10.12%, 1.38%, 54.8%, and 33.7%. Moreover, the total amount of overexploited groundwater was estimated to be 30.41 × 10⁸  m³ (average annual decrease = 1.69 × 10⁸  m³ ). Overall, the proposed identification model was shown to be applicable to agricultural irrigation areas, thereby offering promising implications.