Groundwater contamination analysis using Fuzzy Water Quality index (FWQI): Yazd province, Iran

Fuzzy Water Quality Index (FWQI) was applied in order to assess the degree of drinking water resources in Yazd province, Iran. This study has also offered the creation of a new fuzzy water quality index (FWQI) to evaluate this tool’s applicability. 12 chemical parameters including toxic and non-toxic heavy metals measured in 71 groundwater samples collected from drinking water resources in rural areas were used. In FWQI, input data are categorized into three linguistic terms (“Desirable” or “Low”, “Acceptable” or “Medium” and “Not-acceptable” or “High”) based on water quality standards for drinking water, Whereas the output data are categorized into five classes (“Poor”, “Fair”, “Medium”, “Good” and “Excellent”) based on water quality index (WQI). The results show that 8 groundwater samples were classified in the “Excellent” class with a certainty level of 5.33-76.67%, 41 samples in the “Good” group with a certainty level of 8.5-96.5%, 8 samples were in the “Medium” category with a certainty level of 14-93.5%, 1 sample in the “Fair” level with a certainty level of 36.5%, and 13 samples were classified in the “Poor” class with a certainty level of 54.8-81.5% for potable purposes. The proposed Index can be a useful tool to be used in decision-making and environmental.