Nowadays, due to population growth, agricultural development in arid and semi-arid areas, industrialization and urbanization, uneven spatial and temporal distribution of fresh water, the reduction of water quality, climate change, limited knowledge and cultural awareness, providing safe water has become one of the major challenges that has increased by inefficient management and wrong planning, competition for limited water resources amongst different users with diverse purposes. In the present study the measuring and monitoring sustainability of water resources system has been discussed by using an integrated and systematic approach. In order to get familiar with the basic concepts and principles of research to identify Kor-Sivand river basin as a case study, field visits and investigation of earlier studies and documents have been performed. Afterward, for identifying and analyzing the key stakeholders, a series of interviews and meetings were performed. After identifying and prioritizing key issues and problems in the basin, the issues, problems and factors causing problems have been investigated by using a DPSIR framework. In the next step, the extracted indicates and indices for assessing the situation in the region in recent years have been assessed by collected comprehensive data and information. In the next phase conceptual model has been built based on the performed assessment, causal loops and relationship amongst different sectors, the dominant dynamics, feedback, archetypes of the basin. In the final step, based on the created conceptual model, the indicators have been extracted for assessing the sustainability of water resources system by simulation model using a system dynamics approach. Based on the used methodology in this study, the impact of the in past scenarios such as changes in precipitation, surface water allocation and cultivated area have been developed for evaluation of the development trends in the basin. The results showed that the main causes of the problems in water resources system, environmental and social-economic contexts of Kor-Sivand river basin could be found in the mismanagement in the planning and allocation of water resources, improper withdrawals from groundwater resources, inadequate agricultural development, low crop yield and water efficiency, lack of appropriate of industrial development and the overload on consumption of surface water resources in upstream of the basin. However, population growth, migration from rural to urban areas, drought have exacerbated the consequences of these factors. The over exploitation of water resources for agricultural purposes has influenced highly the water stress in the basin. By elaborating the efficient policies with considering the various aspects of sustainable development can prevent the major problems on water resources in the basin and return the system stability to the region's water resources.
