Author(s): Iman Karimirad, Kumars Ebrahimi, Shahab Araghinejad
Linked Author(s): Iman Karimirad
Keywords: Confined aquifer, Falkenmark Indicator, Golestan Province, phreatic aquifer, water scarcity
Abstract: Sustainability of aquifers is a necessary term for the long-term utilization of groundwater resources. Groundwater sustainability indicators maintain the sustainable management of groundwater resources and help to analyze human impacts on groundwater systems. In this paper, the sustainability of phreatic and confined aquifers in multilayer groundwater system have been evaluated. Assessing sustainability in such groundwater systems can be complicated due to the different effects of recharge and discharge processes on each layer. For this purpose, some indicators were selected based on their feasibility in the study area because they proved to be the most reliable. The indices were applied to a 4700 km� alluvial aquifer located in Golestan province, northern Iran, which has semi-arid climate conditions. Results have proven that the region is facing water scarcity and the aquifer is undergoing intensive use. As a result, in spite of detecting no significant trend in the precipitation data, there were descending trends in the water table and piezometric level of phreatic and confined aquifers, respectively. According to the results aquifer sustainability index of phreatic and confined layers were 0. 89 and 1. 01, respectively that means both layers are unsustainable. Confined layer's condition is worse although the issue has been covered by non-renewable groundwater resources. Phreatic aquifer is also threatened by salty salt-water intrusion. Of course, both layers can be recovered soon. Altogether changing economic axis of the region from agriculture to less water demand sectors such as industry and services or at least cropping patterns is highly advised. Eventually, application of the methodology described here may be proved useful for the evaluation of similar systems in semi-arid climates
Year: 2017