Spatial analysis of groundwater quality for drinking purpose in Sirjan Plain, Iran by fuzzy logic in GIS

Abstract

At present, due to shortage of water resources, especially in arid and semiarid areas of the world such as Iran, exploitation of groundwater resources with suitable quality for drinking is of high importance. In this regard, contamination of groundwater resources to heavy metals, especially arsenic, is one of the most important hazards that threaten human health. The present study aims to develop an approach for presenting the groundwater quality of Sirjan city in Kerman Province, based on modern tools of spatial zoning in the GIS environment and a fuzzy approach of evaluating drinking water in accordance with the standards of world health organization (WHO). For this purpose, qualitative data related to 22 exploitation wells recorded during 2002 to 2017 were used. In addition, fuzzy aggregate maps were prepared in two scenarios by neglecting and considering arsenic presence in groundwater resources. The results showed a decrease in groundwater quality over time. More specifically, neglecting the presence of arsenic, in 2002, all drinking wells in the area were located in an excellent zone, while in 2017 a number of operation wells were located in the good and medium zone. Also, the final map, considering the presence of arsenic as a limiting factor of drinking water, indicated that parts of the southern regions of the plain would be the best place to dig wells for drinking water. Therefore, the use of new methods can contribute significantly to the usage of groundwater aquifers and provide a good view of the aquifer water quality.