In the context of Yangtze River Delta integration and increasingly binding constraints on water resources

this study develops a county-level assessment framework to evaluate the water resources carrying capacity of Jiashan County and identify potential pathways for its improvement. Based on water resources and aquatic-environment monitoring data from2020 to 2024

a Pressure-State-Response index system was established. Indicator weights were determined by combining the analytic hierarchy process with the entropy weight method

and the technique for order preference by similarity to an ideal solution was applied to calculate the annual composite carrying-capacity index and determine the corresponding carrying-capacity levels. Several management scenarios

including improvements in water-use efficiency

increased utilization of non-conventional water resources

and reductions in water-distribution network leakage

were also developed to evaluate the effectiveness of alternative management strategies. The results show that the composite water resources carrying-capacity index of Jiashan County increased from 0. 62 in 2020 to 0. 71 in 2024. Throughout the study period

the index remained within the moderate carrying-capacity range of 0. 60—0. 80 and gradually approached the adequate-capacity threshold of 0. 80.Under the integrated scenario

the composite index approached 0. 80

and the magnitude of improvement was greater than that achieved under any individual measure. The proposed method establishes a quantitative link between carrying-capacity diagnosis and the comparative evaluation of management strategies

thereby providing technical support for refined water resources management at the county level in the Yangtze River Delta.