From mine drainage to river lifeline: An ecological indicator-driven framework for circular water management and SDG synergies in mining basins

• Novel framework translates ecological indicators into optimal mine water reuse. • Coupled models assess mine water impact on flow, quality & vegetation indicators. • Achieved target ecological flows and significant water quality improvements. • NbS approach links water reuse efficiency to ecological corridors and SDGs. • Provides transferable solutions for balancing restoration & resources in mining areas. This study aims to transform mine water from an environmental liability into a strategic resource for ecological restoration and Sustainable Development Goal (SDG) achievement in mining basins, by developing and applying an ecological indicator-driven framework for managing circular hydrosystems and optimizing flow allocation. Addressing water quality heterogeneity and ecological flow needs in the Yellow River Basin’s Wulanmulun River, we integrated traditional hydrological methods (Tennant, FDC, RVA)-serving as baseline flow regime indicators-with a novel dynamic water-energy-ecology coupling model incorporating resource recovery potential metrics. This approach simulates the effects of treated mine water reuse, evaluating performance against key ecological indicators, including targeted ecological flow metrics (5.8 m 3 /s wet, 1.56 m 3 /s dry seasons), water quality indicators (COD, NH 3 -N reductions), and vegetation health indicators (water demand met via modified Penman-Monteith accounting for mining impacts). Furthermore, a generalized Nature-based Solutions (NbS) framework links mine water utilization efficiency to basin-scale ecological corridor design indicators (channel meandering) and establishes transferable resource-byproduct ratio indicators. Application demonstrated significant improvements in ecological indicators: achieving target flows, reducing COD by 7 % and NH 3 -N by over 40 %, and meeting vegetation water demand (6.26 × 10⁶ m 3 ). The framework quantified trade-offs involving land use change indicators (reduced cropland/grassland) and channel morphology indicators (increased meandering). This research advances prior work by embedding circular economy principles directly into ecological indicator-based flow allocation, positioning mine water reuse as a vital tool for enhancing ecosystem health indicators and achieving multiple SDGs. This indicator-centric NbS approach offers a transferable blueprint, validated through sensitivity analysis, for balancing ecological restoration and sustainable resource management in mining regions globally, providing scalable solutions assessed through tangible ecological indicator improvements.