Integration of groundwater into China's south-north water transfer strategy

Groundwater supplies fresh water for drinking and irrigation and sustains the health of ecosystems. Although the serious consequences caused by unsustainable depletion of groundwater have been widely reported, restricting pumping in exhausted aquifers requires identifying alternative water sources, determining how much water can be made accessible to avert the groundwater crisis and formulating water allocation regulations to achieve regional water sustainability. It is perceived that groundwater management needs integrated action considering environmental and socioeconomic systems; however, how a coupled socio-environmental system can be captured and quantified, and how this scientific evaluation is elicited and structured in policy making and implementation processes are still unclear. Here, we propose an integrated quantification framework and a revised policy-making procedure after examining the detailed planning for the groundwater pumping control policy as part of China's South-to-North Water Transfer Project and identifying the shortcomings of the policy. This quantification framework represents the iterative feedback loops between environmental and socioeconomic systems and provides both high-resolution and aggregated indications, that serve as instruments to evaluate the change in the water resource system and the rationality of water allocation plans through projections. Furthermore, our study demonstrates that integrated management needs the participation of scientists and the public, particularly in the discussion of formulating policy drafts among central and local stakeholders, which is helpful for sound decision making and coordination among science, policy making and practice.