Sustainability indices to evaluate groundwater adaptive management: a case study in California (USA) for the Sustainable Groundwater Management Act

The Sustainable Groundwater Management Act (SGMA) enacted in California (USA) outlines legal standards to regulate groundwater management. A key requirement of SGMA is local-scale adaptive management, which requires evaluation of measurable objectives defined by local water users. The objective of this study is to illustrate a groundwater sustainability framework using performance indicators and groundwater-level elevation records that may be used to quantify objective management strategy outcomes. Application of the framework to groundwater basins in the Central Valley identified spatial variability in groundwater-basinsustainability indices, attributed to complex interactions between climate and groundwater use. Further, a temporal assessment of performance indicators documented the utility of the framework to evaluate the performance of adaptive management implementations. The proposed framework can be used to inform management decisions and identify future intervention management strategies.