Evaluation of Treated Water at Three Adjacent Water Treatment Stations in Al-Hilla City , Iraq by Using CCME Water Quality Index

In this study, many water quality indices are reviewed. The Canadian Council of Ministers of the Environment (CCME), Water Quality Index (WQI) is used in the assessment of three adjacent water treatment stations. These stations are in Al-Hilla City in Iraq. They are all supplied with raw water from Shatt Al-Hill River. For determining the water quality of these water treatment stations, eight physical and chemical parameters are estimated. The considered parameters are Alkalinity (Alk), Turbidity (Turb.), Chloride (Cl), pH, Magnesium (Mg), Electrical Conductivity (EC), Calcium (Ca) and Total Hardness (TH). Treated water samples were collected and tested regularly for 6 months from the three stations. The calculated results for water quality reveal that all selected water treatment stations are good according to classification of CCME WQI. All the estimated values of the chemical and physical parameters concerning the studied water treatment stations are ranging within the Iraqi standards except turbidity.


INTRODUCTION
Water is one of the most indispensable resources hence life is not possible on this planet without water.A study conducted by Yisa et al. (2012) showed that the accelerated global population and the rapid progress of industrialization in different fields throughout the last four decades cause an urgent need for fresh water.The requirements of developing health aspects and the necessary human right issues imply the availability of sufficient safe water.Many diseases caused by the lack of safe water sources, insufficient sanitation and poor hygiene result in 3.4 million victims (most of them are children) a year (Ahuja, 2009).Surface waters can be evaluated with respect to quality and pollution by considering water quality parameters which are determined by processing certain sampled data and presenting results to specialists.Conditions of water quality can simply be evaluated by using methods depending on a concept known as Water Quality Index (WQI) (Yisa et al., 2012;Alobaidy et al., 2010).WQI is an effective indicator for presenting information about water quality to interested persons like ordinary citizens and policy planners (Yisa and Jimoh, 2010).It therefore, becomes an important parameter for evaluating and managing the surface water.WQI can be defined as a rating, which gathers the effects of all parameters of water quality into a single value (Yisa and Jimoh, 2012).It is commuted for deciding the surface water suitability for the purposes of human consumption (Atulegwu and Njoku, 2004).Horton (1965) was the first person who used the concept of water quality.
Many studies had been conducted on water to evaluate its quality by using water quality indices.Here are some examples of these indices.A study achieved by Sharifi (1990) had used the US National Sanitation Foundation Water Quality Index (NSFWQI) to calculate the quality of water.Canadian Council of Ministers of the Environment Water Quality Index (CCMEWQI) had been adopted in the assessment of water quality (Lumb et al., 2002).British Columbia Water Quality Index (BCWQI) and Oregon Water Quality Index (OWQI) were used by Debels et al. (2005), Kannel et al. (2007) and Abbasi (2002) to evaluate the water qualities in their studies.
In this study CCME WQI has been considered, thus recent works using this index have been reviewed.Al-Janabi et al. (2012) showed according to CCME WQI, that the water quality of Tigris River in Iraq had ranged between 37 and 42 in some regions along its flow.According to CCME water quality classification, the water quality of the river in those regions was considered to be poor and this was due to the effects of local pollution.Gyamfi et al. (2013) in his study on Aboabo River in Ghana had determined the overall WQI of five different stations on this river to be 17.05 which laid it within the poor classification according to CCME WQI.Using CCME WQI, a study conducted by Munna et al. (2013) on Surma River in Bangladesh, showed that the value of WQI was 15.78 which indicated that water quality of that river was Poor and revealingly impaired near Sylhet city.Agrama and El-Sayed (2013) had conducted a study on different locations at each canal of an agricultural area in Western Delta-Egypt.The water quality in the studied area was classified as marginal according to CCME WQI.

MATERIALS AND METHODS
Study area: This study is conducted to assess some water treatment stations in Al-Hilla City by using CCME WQI.Al-Hilla City is located in the middle of Iraq.The surface water of this city is Euphrates River and all the water treatment stations approached in this study are conventional.
Sampling: Three water treatment stations in Al-Hilla City are considered in this study.These treatment stations are supplied with raw water from Shatt-Al-Hilla which is a branch of Euphrates River.They are supplying drinking water to three separate areas along the flow of Shatt-Al-Hilla.Samples of drinking water were collected from these stations for the period from October 2013 to March 2014.Samples were immediately processed after collection for physical and chemical properties.Eight parameters were used to calculate the water quality index.These parameters were pH, Total Hardness (TH), Calcium (Ca), Alkalinity (Alk), Turbidity (Turb.),Electrical Conductivity (EC), Magnesium (Mg) and Chloride (Cl).The Iraqi recommended Guidelines for drinking water specifications are stated in Table 1.

Measurement of water quality using CCME WQI:
WQI can be defined as a mathematical tool transforming large quantities of data obtained from physical and chemical properties of water into a single number representing the level of water quality (Bharti and Katyal, 2011).In this research CCME WQI was used to calculate the water quality.This index can be determined as follows (CCME, 2001): • F1 is called Scope which represents the percentage of variables that do not meet their objectives at least once during the interval under consideration ("failed variables"), relative to the total number of variables measured: • F3 is called Amplitude, which represents the deviations of the failed tests from their objectives.
It is determined as follows: o The term "Excursion" represents the number of times that certain concentration is different from the objective.When the value of the test is less than the objective, Excursion is given by: When test value is greater than the objective, Excursion is given by: o The sum of exertions of individual tests divided by the total number of tests is called normalized sum of excursions (nse) and is computed as follows: o F3 is a function of nse and is given by: Finally CCME WQI is calculated as follows: The water quality is ranked according to CCME WQI as stated in Table 2.

RESULTS AND DISCUSSION
The calculated results for pH varied from 7.5 to 7.8 in station (1), 7.6 to 8.05 in station (2) and 7.4 to 8 in

CONCLUSION
The calculated results showed that the water quality of treated water at all stations were good according to the CCME classification during the study period.All values of selected parameters were within the Iraqi standards for drinking water except turbidity.

Table 1 :
Iraqi standards for drinking water, 2001