This study aimed to analyze the growth limit of the water resource system in the Kor-Sivand Basin by integrating a water balance model with the pressure and support framework. Population growth, unsustainable agricultural development, inefficient management, and climate change intensified the water crisis and made it necessary to assess the hydrological balance alongside economic, social, and environmental dimensions. Due to the lack of official data after 2011, a water balance model based on regression relationships was developed for the agricultural, industrial, and service sectors. Pressure and support indicators were calculated, and the system's growth limit was derived from the ratio of the mean standardized support indicators to the mean pressure indicators. Based on the findings, the basin's carrying capacity index decreased from 1.05 in 2001 to 0.95 in 2016, crossing the equilibrium threshold, while the relative water stress index increased by 1.58 units. This trend indicated that the basin had entered a phase of gradual degradation and was approaching a collapse threshold. The dynamic balance of water consumption between agricultural and ecological sectors highlighted the necessity of integrated water management. In the Kor-Sivand Basin, merely changing the development pattern was not sufficient; local solutions based on accurately identifying the system's growth limit and reducing pressures must be developed and implemented.