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
Keywords: 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.

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.


Abhishek, S. & Khambete, A. (2013). Statistical analysis to identify the main parameters to the wastewater quality index of CETP: A case study at VAPI, Gujarat, India. Journal of Environmental Research And Development, 7(3), 1294-1299.

Abtahi, M., Golchinpour, N., Yaghmaeian, K., Rafiee, M., Jahangiri-rad, M., Keyani, A. & Saeedi, R. (2015). A modified
drinking water quality index (DWQI) for assessing drinking source water quality in rural communities of Khuzestan Province, Iran. Ecological Indicators, 53, 283-291.

Ahmed, A. H., & Ali, D. S. (2009). Investigation of chemical and radioactive contamination level of the drinking water resources in Erbil City. Journal of Environmental Studies, 1, 9-18.

Ali, L. A. (2010). Seasonal variation in physico-chemical propertice and zooplankton biomass in greater zab river-Iraq. Jordan Journal of Biological Sciences, 3(3), 115-120.

Alobaidy, A. H. M. J., Abid, H. S. & Maulood, B. K. (2010). Application of water quality index for assessment of Dokan lake ecosystem, Kurdistan region, Iraq. Journal of Water Resource and Protection, 2(9), 792-798.

Apha, L., Clesceri, A. & Greenberg, A. (1998). Standard Methods for the Examination of Water and Wastewater. 20th ed. Washington, DC: American Public Health Association.

Aris, A. Z., Tengku-Ismail, A. E. T. H., Harun, R., Firuz-Ramli, M., Abdullah, R., Azhar, S. C. & Juahir, H. (2015). Environmental forensics 2015 classification of river water quality using multivariate analysis. Procedia Environmental Sciences, 30, 79-84.

Aziz, F. H. (2011). Checklist of the algal flora survey in Iraqi Kurdistan region Iraq with particular reference to habitats. Zanco Journal of Pure and Applied Science, 23(3):30-72.

Aziz, S. Q. (2009). Treatment of Greater-Zab Water by Direct Filtration. Paper Presented at the Thirteenth International Water Technology Conference.

Baghapour, M. A. & Shooshtarian, M. R. (2018). Assessment of groundwater quality for drinking purposes using water quality index (WQI) in Shiraz, Iran (2011 to 2015). Iranian Journal of HealthSafety and Environment, 5(1), 888-893.
Bapeer, U. H., Al-Naqishabandi, L. A., Toma, J. J. &, Ismail, H. A. (2006).

Study some physico-chemical and bacteriological variables of both drinking water purification projects (Ifraz and Ainkawa) in Erbil,Iraq. Zanco, Journal of Pure and Applied Sciences/Salahaddin University, 18(3), 19-21.

Berisha, F. & Goessler, W. (2013). Investigation of drinking water quality in Kosovo. Journal of Environmental and Public Health, 2013, 9.

Bharti, N. & Katyal, D. (2011). Water quality indices used for surface water vulnerability assessment. International Journal of Environmental Sciences, 2(1), 154.

Bhuiyan, M. A. H., Rakib, M. A., Dampare, S. B., Ganyaglo, S. & Suzuki, S. (2011). Surface water quality assessment in the central part of Bangladesh using multivariate analysis. KSCE Journal of Civil Engineering, 15(6), 995-1003.

Boyacioglu, H. (2007). Development of a water quality index based on a European classification scheme. Water Sa, 33(1), 101-106.

Gharibi, H., Sowlat, M. H., Mahvi, A. H., Mahmoudzadeh, H., Arabalibeik, H., Keshavarz, M. &. Hassani, G. (2012). Development of a dairy cattle drinking water quality index (DCWQI) based on fuzzy inference systems. Ecological Indicators, 20, 228-237.

Goher, M. E., Hassan, A. M., Abdel-Moniem, I. A., Fahmy, A. H. & El-sayed, S. M. (2014). Evaluation of surface water quality and heavy metal indices of Ismailia Canal, Nile River, Egypt. The Egyptian Journal of Aquatic Research, 40(3), 225-233.

Goran, S. M. (2010). Evaluation of Ifraz water treatment plants in Erbil city-Iraq. Journal of Science Education, 23(4), 19-22.

Heydari, M. M., Abbasi, A., Rohani, S. M. & Hosseini, S. M. A. (2013). Correlation study and regression analysis of drinking water quality in Kashan City, Iran. Journal of Science Education, 10(3), 10.

Horton, R. K. (1965). An index number system for rating water quality. Journal of Water Pollution Control Federation, 37(3), 300-306.

Hoseinzadeh, E., Khorsandi, H., Wei, C. & Alipour, M. (2015). Evaluation of aydughmush river water quality using the national sanitation foundation water quality index (NSFWQI), river pollution index (RPI), and forestry water quality index (FWQI). Desalination andWater Treatment, 54(11), 2994-3002.

Hurley, T., Sadiq, R. & Mazumder, A. (2012). Adaptation and evaluation of the Canadian council of ministers of the environment water quality index (CCME WQI) for use as an effective tool to characterize drinking source water quality. Water Research, 46(11), 3544-3552.

Issa, H. M. (2014). An initial environmental assessment for the potential risk of the developing industry impact on the surface water resources in the Kurdistan Region - Iraq. Journal of Garmian University, 1(Special Issue), 35-48.

Issa, H. M. (2017). Evaluation of water quality and performance for a water treatment plant: Khanaqin city as a case study. Journal of Garmian University, 3(No.12 Special Issue), 802-821.

Kafia, M. S., Slaiman, G. M. & Nazanin, M. S. (2009). Physical and chemical status of drinking water from water treatment plants on Greater Zab River. Journal of Applied Sciences and Environmental Management, 13(3), 144-216.

Krishan, G., Singh, S., Kumar, C., Garg, P. & Suman, G. (2016). Assessment of groundwater quality for drinking purpose by using water quality index (WQI) in Muzaffarnagar and Shamli Districts, Uttar Pradesh, India. Hydrol Current Research, 7(227), 2.

Magesh, N. S., Krishnakumar, S., Chandrasekar, N. & Soundranayagam, J. P. (2013). Groundwater quality assessment
using WQI and GIS techniques, Dindigul district, Tamil Nadu, India.Arabian Journal of Geosciences, 6(11), 4179-4189.

Monjerezi, M. & Ngongondo, C. (2012). Quality of groundwater resources in Chikhwawa, lower shire Valley, Malawi. Water Quality, Exposure, and Health, 4(1), 39-53.

Nanekely, M., Scholz, M. & Al-Faraj, F. (2016). Strategic framework for sustainable management of drainage systems in semi-arid cities: An Iraqi case study. Water, 8(9), 406.

Oke, A. O., Sangodoyin, A. Y. & Omodele, T. (2017). Classification of river water quality in Ogun and Ona River Basins, Nigeria using CCME framework: Implications for sustainable environmental management. Cogent Environmental Science, 3(1), 1295696.

Pejman, A. H., Bidhendi, G. R. N., Karbassi, A. R., Mehrdadi, N. & Bidhendi, M. E. (2009). Evaluation of spatial and seasonal variations in surface water quality using multivariate statistical techniques. International Journal of Environmental Science and Technology, 6(3), 467-476.

Poonam, T., Tanushree, B. & Sukalyan, C. (2013). Water quality indices—important tools for water quality assessment: A review.International Journal of Advances in Chemistry, 1(1), 15-28.

Ramesh, S., Sukumaran, N., Murugesan, A. G. & Rajan, M. P. (2010). An innovative approach of drinking water quality index - A case study from Southern Tamil Nadu, India. Ecological Indicators, 10(4), 857-868.

Rickwood, C. J. & Carr, G. M. (2008). Development and sensitivity analysis of a global drinking water quality index. Environmental Monitoring and Assessment, 156(1), 73.

Sadiq, R., Haji, S. A., Cool, G. & Rodriguez, M. J. (2010). Using penalty functions to evaluate aggregation models for environmental indices. Journal of Environmental Economics and Management, 91(3), 706-716.

Said, A., Stevens, K. D. & Sehlke, G. (2004). An innovative index for evaluating water quality in streams. Environmental Management, 34(3), 406-414.

Sharda, A. & Sharma, M. (2013). Water quality assessment of Swan River in Himachal Pradesh, India. International Journal of Environmental Sciences, 4(3), 402-414.

Shareef, K. M. & Muhamad, S. G. (2008). Natural and drinking water quality in Erbil, Kurdistan. Current World Environment, 3(2), 227-238.

Shrestha, S. & Kazama, F. (2007). Assessment of surface water quality using multivariate statistical techniques: A case study of the Fuji river basin, Japan. Environmental Modelling and Software, 22(4), 464-475.

Simões, F. D. S., Moreira, A. B., Bisinoti, M. C., Gimenez, S. M. N. & Yabe, M. J. S. (2008). Water quality index as a simple indicator of aquaculture effects on aquatic bodies. Ecological Indicators, 8(5), 476-484.

Srinivasamoorthy, K., Chidambaram, S., Prasanna, M. V., Vasanthavihar, M., Peter, J. & Anandhan, P. (2008). Identification of major sources controlling groundwater chemistry from a hard rock terrain — A case study from Mettur taluk, Salem district, Tamil Nadu, India. Journal of Earth System Science, 117(1), 49-58.

Tahri, M., Benyaïch, F., Bounakhla, M., Bilal, E., Gruffat, J. J., Moutte, J. & Garcia, D. (2005). Multivariate analysis of heavy metal contents in soils, sediments, and water in the region of Meknes (central Morocco). Environmental Monitoring and Assessment, 102(1), 405-417.

Tebbutt, T. H. Y. (1997). Principles of Water Quality Control. Oxford: Butterworth-Heinemann.

Tiwari, A. K., De Maio, M., Singh, P. K., Amanzio, G. & Lavy, M. (2015). Surface water quality assessment for the suitability of drinking and domestic purposes in West Bokaro coalfield, India. Rendiconti Online Della Società Geologica Italiana, 35, 13-16.

Tiwari, T. & Mishra, M. (1985). A preliminary assignment of water quality index of major Indian rivers. Indian Journal of Environmental Protection, 5(4), 276-279.

Toma, J. J. (2013). Evaluating raw and treated water quality of greater Zab river within Erbil city by index analysis. International Journal of Emerging Technologies in Computational and Applied Sciences, 12, 147-154.

Toma, J. J., Assad, Z. S. & Baez, D. R. (2013). Water quality assessment of some well water in Erbil city by quality index, Kurdistan REGIONIraq. Journal of Advanced Laboratory Research in Biology, 4(4), 125-130.

Tyagi, S., Sharma, B., Singh, P. & Dobhal, R. (2013). Water quality assessment in terms of water quality index. American Journal of Water Resources, 1(3), 34-38.

Vasanthavigar, M., Srinivasamoorthy, K., Vijayaragavan, K., Rajiv Ganthi, R., Chidambaram, S., Anandhan, P. &. Vasudevan, S. (2010). Application of water quality index for groundwater quality assessment: Thirumanimuttar sub-basin, Tamilnadu, India. Environmental Monitoring and Assessment, 171(1), 595-609.

Wanda, E. M. M., Mamba, B. B. & Msagati, T. A. M. (2016). Determination of the water quality index ratings of water in the Mpumalanga and North West Provinces, South Africa. Physics and Chemistry of the Earth, Parts A/B/C, 92, 70-78.

Wang, X., Zhang, F. & Ding, J. (2017). Evaluation of water quality based on a machine learning algorithm and water quality index for the Ebinur Lake Watershed, China. Scientific Reports, 7, 12858.

World Health Organization. (2004). Guidelines for Drinking-water Quality: Recommendations. Vol. 1. Geneva: World Health Organization.

World Health Organization. (2011). Guidelines for Drinking-water Quality. Geneva: WHO Publications.
How to Cite
Issa, H., & Alrwai, R. (2018, December 26). Long-Term Drinking Water Quality Assessment Using Index and Multivariate Statistical Analysis for Three Water Treatment Plants of Erbil City, Iraq. UKH Journal of Science and Engineering, 2(2), 39-48. https://doi.org/https://doi.org/10.25079/ukhjse.v2n2y2018.pp39-48
Research Articles