Long-Term Drinking Water Quality Assessment Using Index and Multivariate Statistical Analysis for Three Water Treatment Plants of Erbil City, Iraq


  • Hayder Mohammed Issa Department of Geography, College of Human Sciences, University of Garmian, Kalar, Sulaimaniyah Province 46021, Kurdistan Region - F.R. Iraq http://orcid.org/0000-0002-0857-0097
  • Reem Ahmed Alrwai Department of Dams & Water Resources, College of Engineering, Salahaddin University-Erbil, Erbil, 44002, Kurdistan Region - F.R. Iraq




physicochemical parameters, bacteriological parameters, drinking water quality index DWQI, water treatment plant, Erbil City


Safe source of drinking water is always considered as an essential factor in water supply for cities and urban areas. As a part of this issue, drinking water quality is monitored via a useful scheme: developing drinking water quality index DWQI. DWQI is preferably used as it summarizes the whole physicochemical and bacteriological properties of a drinking water sample into a single and simple term. In this study, an evaluation was made for three drinking water treatment plants DWTPs named: Efraz 1, Efraz 2 and Efraz 3 that supply drinking water to Erbil City. The assessment was made by testing thirteen physicochemical and two bacteriological parameters during a long period of (2003 – 2017). It has been found that turbidity, electrical conductivity EC, total alkalinity, total hardness, total coliform and fecal coliform have more influence on drinking water quality. DWQI results showed that the quality of drinking water supplied by the three DWTPs in Erbil City fallen within good level. Except various occasional periods where the quality was varying from good to fair. The quality of the drinking water supply never reached the level of marginal or poor over the time investigated. The applied hierarchical clustering analysis HCA classifies the drinking water dataset into three major clusters, reflecting diverse sources of the physicochemical and bacteriological parameter: natural, agriculture and urban discharges.


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Author Biographies

  • Hayder Mohammed Issa, Department of Geography, College of Human Sciences, University of Garmian, Kalar, Sulaimaniyah Province 46021, Kurdistan Region - F.R. Iraq

    Hayder M. Issa is an assistant professor at University of Garmian, he has completed B.Sc. degree in Chemical Engineering from University of Baghdad, Iraq in 1992 and Master’s degree in Chemical Engineering from the same University in 1995. The PhD degree is in Process and Environmental Engineering from University of Toulouse III (Université Paul Sabatier), INPT, Toulouse, France, in 2013, and is in the field of mass transfer and flow behavior in water treatment tank. He has academic and research experience related to various topics like plant design, reaction engineering, environmental pollution, oil & gas processing, process modeling & simulation and water quality & treatment.

  • Reem Ahmed Alrwai, Department of Dams & Water Resources, College of Engineering, Salahaddin University-Erbil, Erbil, 44002, Kurdistan Region - F.R. Iraq

    Reem A. Alrawi obtained her Bachelor's Degree in the field of Chemical Engineering from the Al-Nahrain University, Iraq in 1996 and Master degree in the field of Environmental Engineering from the University of Baghdad, Iraq in 2003. The PhD degree is in Environmental Technology from Universiti Sains Malaysia in 2012. Since 1996 she is as researcher in the field of Environmental Engineering at many research centers and
    companies in Iraq, Jordan and Malaysia. Her research interests are water and wastewater treatment.


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Research Articles

How to Cite

Long-Term Drinking Water Quality Assessment Using Index and Multivariate Statistical Analysis for Three Water Treatment Plants of Erbil City, Iraq. (2018). UKH Journal of Science and Engineering, 2(2), 39-48. https://doi.org/10.25079/ukhjse.v2n2y2018.pp39-48