Evaluating and Optimizing Water Resources Carrying Capacity in Anji County, China

Water resources’ carrying capacity (WRCC) is crucial for sustainable development, linking natural resources with social and economic systems. Although Anji County in China has relatively abundant water, uneven distribution, strong seasonality, and rising demand from industrialization and population growth have kept the system close to overload. Using a comprehensive evaluation and optimization framework, this study assessed WRCC from 2015 to 2023. Results show the county has long operated near its threshold, with water shortages projected to reach 23% by 2025, though pressures may ease by 2030. Key constraints include high industrial water use, limited reuse of treated wastewater, and low per capita availability. Model simulations suggest that optimized allocation of surface water, groundwater, and reclaimed water could improve carrying capacity by up to 30%. These findings highlight the need for industrial upgrading, water-saving measures, and expanded wastewater reuse, providing practical guidance for resource management in Anji County and a useful reference for other regions facing similar challenges.