Evaluation of parameters affecting the Water Quality Index in the Al-Basel Dam Lake in Tartus

Abstract

The water quality indexes (WQI) widely used to assess physical, chemical and biological water characteristics. WQI calculation requires the collection and analysis of a large water quality dataset from the water source, spatially and temporally. Several WQIs have been developed, which quantify in a single dimensionless number the surface or groundwater quality, and include important parameters that used for WQI calculation. In this study, the Canadian Council of Ministers of the Environment WQI (CCME QWI) was used to evaluate the parameters that most important in WQI value for Al-Basel dam lake in Tartus for drinking purposes. The data of samples analysis taken from the site in the middle of the lake  for the parameters: Temperature (°C), pH, conductivity (Con.), dissolved oxygen (DO), total hardness (TH), ammonium (NH₄⁺), nitrite (NO₂^-), nitrate (NO₃^-), phosphate (PO₄^-), chloride (Cl^-), sulphate (SO₄^-2), biochemical oxygen demand (BOD) and fecal coliform bacteria (FCB). WQI was calculated on an annual basis. The results indicated that the lake is exposed to microbiological pollution that affects the value of WQI, the classification of water quality is bad. While with the exception of (FCB), WQI is fair to good. It also showed the percentage of parameters that exceed the guideline (F1) significantly correlated with WQI, the correlation coefficient was 0.95, while the correlation coefficient was 0.89 for the percentage of individual testes within each parameter that exceed the guideline (F2), and the extent to which the fail test exceeds the guideline (F3) the correlation coefficient was 0.79.  Turbidity, dissolved oxygen, biochemical oxygen demand and phosphate are the parameters that significantly influence the value of WQI and should be consider when developing engineering solutions to protect the AL Basel dam lake from pollution.