Model-based water footprint accounting framework to evaluate new water management policies

Abstract

Countries' water-related programs mainly align with water scarcity and climate change adaptation. However, a central point about the proposed strategies is the effectiveness degree of the introduced measures and their proportionality and coordination with the other goals of the system. This study uses a combination simulation approach using the SWAT model and water footprint accounting framework to investigate water management activities' effects and rebound effects on water resources sustainability. The activities included expanding modern irrigation systems, developing rain-fed orchards, watershed management activities, and omitting water-intensive crops. Results show that although the growth of modern irrigation systems reduced water extraction by 50%, this strategy cannot be helpful in water-saving because the actual water use is not controlled and even caused a slight increase in water consumption of 0.6%. This measure also led to a significant reduction in return flow to the aquifer (80%). Results also indicate an intensification of blue water non-sustainability caused by the expansion of rain-fed orchards because of increased actual water use. Watershed management activities raise green water storage by 4%, positively impacting aquifer recharge, which is in line with the objectives of the water sector. However, it cannot be used as an effective strategy to create new water resources to deal with environmental crises such as wetlands restoration. Changing the water-intensive cropping pattern will effectively improve blue water and groundwater sustainability if the rebound effects are controlled. Thus, there will be a water saving of approximately 110 million m3 in water consumption with the alteration of rice cultivation into wheat in the studied basin.