Prospects to the Water Crisis in Iran : Application of System Dynamics Modeling Approach

Water scarcity is a highly complex, multifaceted and dynamic issue, which have become a severe challenge worldwide. While determinants of water scarcity and their direct associations have been heavily discussed in numerous studies, a small number of research have analyzed water scarcity using a system thinking approach. Furthermore, available studies have included only a limited number of determinants and their feedback mechanisms in their analysis of water scarcity which does not represent its actual behavior, resulting in an inaccurate basis for decision making. Contributing to this area of research, our study applies a nexus approach using the System Dynamic Modeling (SDM) method to develop a national-scale model to investigate water scarcity in Iran. The results showed that a substantial water supply-demand gap exists in Iran, with an excess consumption of 62,361 million cubic meters. Climate change was found to be the prime cause of exacerbating water scarcity in Iran, raising evapotranspiration from 70% to 85% in 50 years, and enhancing water demand in various sectors considerably. Simulating the future condition of water scarcity under four scenarios, the results showed that under the business as usual scenario, the gap between water supply and demand will enlarge, leading to water crisis in Iran. Beside this, the results showed that neither supply-side nor demand-side scenarios could solely address water crisis in Iran, and mixed supply-demand side’s interventions, as the most effective policy, should be taken to alleviate water crisis in the country. Overall, the study suggests that the principal of water resource management in Iran should be revisited to include a system thinking management approach. The results can be used as a decision support tool that informs suitable mitigation and adaptation strategies to water scarcity in the country