Water scarcity across the world is caused by climatic change and inefficient management. The agricultural sector utilizes a greater amount of water than any other source and squanders a significant portion of it due to inadequacies. Therefore, the aim of this study was to identify key parameters in social systems that significantly impact hydrological system change and to present the best scenario for agricultural water management. The SD approach was employed in this research to construct a combined framework of policies based on scenarios, which aimed to ensure social sustainability and coupled human-water systems. The model was evaluated using hybrid simulation criteria that consisted of both qualitative and quantitative aspects. For this purpose, the SD model was performed on the Gavshan watershed in the west of Iran, which is calibrated for historic data (2010- 2020) and simulated for the long-term period 2020-2050. The results indicate that the water resources system can not supply water to the growing population in the Gavshan watershed. Moreover, the result of the simulated model showed that in scenarios (3) and (4), the policies of wastewater reuse in agricultural and leakage reduction strategies significantly increase available water resources compared to the per capita water consumption reduction strategy. This result could provide water managers and decision-makers with the most appropriate strategies leading to long-term socio-hydrology systems sustainability in arid and semi-arid regions. It is suggested that national organizations' support should be implemented to prevent the undesired consequences of wastewater reuse in agriculture and reduce treated wastewater risks.
