Assessment of groundwater sustainability and management plan formulations through the integration of hydrogeological, environmental, social, economic and policy indices

Abstract

To protect aquifers, it is necessary to assess their sustainability in the face of current and future events and stresses. In this study, technical, environmental, social, economic, and groundwater sustainability policy indexes were integrated and used to assess the sustainability of aquifers in the Salt Lake catchment. This 92,884.2 km2 catchment, one of the most important second-grade watersheds in Iran in terms of the importance of water resources, is located in Tehran, Markazi, Qazvin, Zanjan, Hamedan, Isfahan, Qom, and Alborz provinces, and comprises 36 aquifers in the basin. Seven quantitative hydrogeological indicators, three qualitative hydrogeology indicators, six environmental indicators, three social indicators, two economic indicators, and one policy indicator were considered. Final sustainability in each dimension (hydrogeological, environmental, social, economic, and policy) and overall sustainability were evaluated with the analytical hierarchy process and Shannon information entropy weighting approach to integrate expert opinion. The final results of sustainability analysis show that in the Salt Lake catchment, eastern aquifers are completely unstable and western aquifers show poor stability. Management scenarios with a 40% and 80% reduction in groundwater abstraction in the framework of the driving force-pressure-status-impact-response model show that a 40% reduction plays no a significant role in improving the quantitative sustainability of aquifers, whereas an 80% reduction in abstraction leads to an improvement of about 25% in quantitative sustainability.