Development and Evaluation of a Water Quality Index for the Iraqi Rivers

Abstract

Water quality evaluation is fundamental for water resources management. Water quality index (WQI) is an accurate and easily understandable method for assessing water quality for different purposes. In this study, the Iraqi water quality index (Iraq WQI) was constructed to be used to evaluate the Iraqi rivers for drinking. For this purpose, some statistical techniques, experts’ advice, literature reviews, and authors’ experience were used. First, the principal component analysis (PCA) method and the modified Delphi method were used to select the most influential water quality parameters and their relative weights. Second, the quality curves of selected parameters were drawn to calculate the WQI scores basing on the water quality standards. Of twenty-seven parameters, six parameters were chosen to be within the index depending on their effect on water quality in order to reflect the specific characteristics of the Iraqi waters. The Iraq WQI was applied to the Tigris River within Baghdad as a case study and for some sites on other Iraqi rivers, and gave acceptable results. Results revealed that the statistical techniques used in this paper can be applied in all Iraqi rivers considering their specific characteristics. Based on the reliability of the Iraq WQI, there is no longer a need to use Indices designed for water for other countries.

Relationships of soil erodibility parameters and water quality indices along Tigris Riverbanks, Baghdad City, Iraq

“…Al-Obaidy et al (2010) proposed that CWQI is decreasing in value because of the various kinds of contaminants entering the basin for natural causes and different practices, such as domestic wastewater, discharge, and river drainage from agriculture along the banks of the river. While the average value of IWQI was good during the two seasons, the same result was obtained by Ewaid et al (2020) when they used IWQI. Ewaid et al (2020) developed IWQI based on six water parameters to reflect the characteristics of the Iraqi waters.…”

“…While the average value of IWQI was good during the two seasons, the same result was obtained by Ewaid et al (2020) when they used IWQI. Ewaid et al (2020) developed IWQI based on six water parameters to reflect the characteristics of the Iraqi waters. Water samples were collected from 10 intakes of water purification plants located along the Tigris River in Baghdad.…”

“…The following steps are taken to establish any water quality index, according to Ewaid et al (2020) and should be followed. First of all, select the water parameters.…”

“…The results showed that the Tigris River's water quality deteriorated downstream of the Tigris River, especially at the Al-Aziziya station in the wet and dry seasons. Furthermore, Ewaid et al (2020) developed a new water quality index for Iraqi Rivers (IWQI). The IWQI was established by considering 27 water parameters based on the Iraqi drinking water standard.…”

Evaluation of Chemical Parameters of Urban Drinking Water Quality along with Health Risk Assessment: A Case Study of Ardabil Province, Iran

“…Water quality indices have been used in recent years to evaluate the quality of water consumed by humans in various studies [ 7 , 8 , 9 , 10 , 11 , 12 ]. Water quality indices can be considered water quality models, as a simplified representation of a complex reality [ 13 ].…”