Author : A. Majeed, Sumayah
journal of kerbala university,
Volume 14, Issue 1, Pages 53-65
Water Quality Indices (WQI's) are tools to determine the conditions of water quality and provide overall summaries of water quality and potential trends of water quality on a simple and scientific basis.
The present research compares the results of the Canadian WQI method with two other water quality index methods (Mierels WQI and Weighted Arithmetic Index) for irrigation and drinking purposes. Six locations were being chosen on the Bani-Hassan River. Monthly parameters of raw water analysis during the period January to December 2015 were obtained to determine water quality indices. These parameters were: pH, EC, TDS, Turbidity, Total Hardness (TH), Ca+2, Mg+2, K+, Na+, Cl-, SO4-2, HCO3-and Sodium Absorption Ratio (SAR).
The results of applying Canadian WQI and Weighted Arithmetic Index (WAI) for assessing the suitability of Bani-Hassan River for drinking purpose showed that; Canadian WQI method is classified water as (Fair) water quality while WAI method results is ranked it as (unsuitable) water for drinking usage.
In the case of the suitability of water for irrigation use, the results of applying Meireles WQI equations showed that the water quality of Bani-Hassan River is classified as a (Moderate Restriction) in water use, while the classification of the water using the Canadian equations was good for irrigation purpose.
When comparing (WQI) results of Canadian technic with two other technics (Weighted Arithmetic Index and Mieriles WQI) it is easy to say that Canadian method gives higher water quality value than the two other methods, in another word,Canadian Water Quality Index considered more elastic, however, the Weighted Arithmetic Index and Mieriles WQI methods utilized if there is need for restrictive control of water using.
Statistical analysis of the two methods (Canadian WQI and Mierels WQI) for irrigation use showed that there is a significant difference between the two technics results at significance level (0.05).