Investigating the Impacts of Restoration Scenarios for Mashhad Aquifer Using Systems Dynamic Approach

The declining trend of groundwater reserves due to the high importance of these resources for water supply has become a major challenge, especially in arid and semi-arid regions such as many plains of Iran. On the other hand, establishing an urban wastewater project will directly impact the aquifer of the plain and intensify the process of reducing these reserves. This study investigates the effect of revival strategies in the framework of sustainable development principles on improving the aquifer reserves under five different scenarios. The Mashhad aquifer was picked as a case study. Simulation of the aquifer was performed using the system dynamics approach and Vensim PLE model during 1362-1420. Sensitivity analysis and calibration of the model were done during the period of 1362 to 1392, and the model was simulated until 1420 for evaluatation of different scenarios. Sensitivity analysis results demonstrated that aquifer volume has the highest sensitivity to the return coefficient of drinking and agricultural sectors. Increasing the pervious surfaces in urban architecture has improved about 16 and 19 percent in the aquifer recharging compared to scenarios 2 and 3. Generally, using methods such as changing agricultural methods, increasing water productivity, and improving urban architecture with a focus on increasing permeable levels, it can reduce the aquifer shortage between 22.0 % to 58.5%, compared to scenario 2. While not paying attention to the proposed methods led to a negative balance, and the aquifer will be in a critical and irreparable situation.