Dynamic Analysis of Sustainable Management Policies of Underground Water Resources Based on Water-Food-Energy Nexus (Case Study: Alborz Province)

According to the ranking of the World Resources Institute, Iran ranks 14th in water stress in the world, and is among the 20 countries with the highest water stress in the world. The current process of extracting underground water resources in Iran is an unstable process and its continuation will cause serious irreparable damage to the quantity and quality of aquifers. The security of underground water resources is considered more complicated in some provinces of Iran due to the degree of dependence on underground water resources. About 85% of the water needed in Alborz province is supplied by relying on ground water sources, and the population growth of Alborz province is more than three percent and twice the average population growth of the country. This has caused Alborz province to suffer unbalanced development in all fields; Alborz water resources are not able to respond to this unbalanced development and this has caused water tension in Karaj metropolis and surrounding cities and even villages. The unbalanced development process of Alborz province in recent years has aggravated the security crisis of underground water resources and water stress. With the growth of demand in the future, the competition for water resources will increase and the sustainable management of underground water resources is considered as a challenge in the region. Among the approaches of sustainable management of water resources, Water-Food-Energy Nexus provides the necessary prerequisites for the sustainable management of existing limited resources in an integrated manner.

The present study deals with the dynamic modeling of sustainable management of underground water resources based on the security of water-food-energy nexus resources and analyzes the solutions of sustainable management of underground water resources according to the trend of population changes, economic growth and the development of renewable energy sources. It is for this purpose, a dynamic model was designed using time series data, and after validation, the model was simulated in a twenty-year horizon. The base year in the model is 2011, and time series data from 2011 to 2016 were used to evaluate the behavioral validity of the model. Validation of the model included goodness of fit tests, dimensional consistency tests, boundary adequacy tests, behavior reproduction tests, and integration error tests. Also, in terms of behavior, the behavior of the model variables was approved by the experts.

According to the results of model sensitivity analysis and feasibility studies of operational plans for water resources management in Alborz province and with the participation of Alborz regional water policy makers, three scenarios to improve the security of underground water resources with regard to the link between the security of water and food resources -Energy was considered: 1- The security of underground water resources based on the optimal exploitation of water supply resources, including the policy of artificial feeding of aquifers: the policy of blocking unauthorized wells and controlling withdrawals. Unauthorized and the policy of building and operating systems for storing and extracting rainwater and gray sewage effluent and reuse, 2- The security of underground water resources based on the management of agricultural water demand, including the policies of the development policy of irrigation systems, the policy of promoting the model suitable cultivation with climatic conditions and ecological power and the policy of reducing agricultural waste during the production period and the policy of developing the performance of agricultural products and the development of mechanized cultivation and 3- the security of underground water resources based on the management of electric energy demand, including the policies of the policy of consumption optimization and Reduction of electrical energy loss, the policy of building a power plant for heat recovery from industrial processes, the policy of exploiting the potential of solar renewable energy was designed and a group of policies were identified. The findings of the WFEN-SD model indicate that the combined policy is the best solution for the sustainable management of underground water resources and includes: artificial feeding of the aquifer 10 million cubic meters annually; Organizing and controlling withdrawal from wells; Exploitation of gray wastewater and reuse and supply of 10% of agricultural water; 10% development of irrigation efficiency with new irrigation systems; 10% reduction in agricultural waste; 10% development of agricultural products yield by seed improvement, plant preservation and pest control and mechanized cultivation support policies; 5% reduction of electrical energy loss in combined cycle power plant and development of solar pumping systems in the agricultural sector.