Environmental Assessment of Water Quality in the Qarraoun Lake: The Investigation of PhysicoChemistry and Microbial Properties

The Qarraoun Lake is the largest artificial reservoir in Lebanon, which is located along the Litani River in the Bekaa plain. It represents the connecting point between the Upper and Lower Litani River Basins. Water collected in the lake is used for multipurpose, and mainly for irrigation, fisheries, power generation, and domestic water use. Recently, the Lake has been witnessing severe deterioration in water quality due to uncontrolled liquid and soil waste disposal in the Upper River Basin. As a result, the pollutants accumulate into the Lake water. Apart from laboratory analysis for water quality, the pollution is obvious through direct observations, smells, and water color and patterns. This paper focuses on assessing the level of pollution in the Lake. Therefore, the physico-chemical and microbiological properties of water were investigated on 15 selected sampling on the representative sites of the Lake. Microbiological and physico-chemical analyses were performed in accordance with the European Standard Methods and World Health Organization (WHO). Multivariate statistical methods (Hierarchical Clustering Analysis: HCA, and Principal Component Analysis: PCA) were applied to figure out the influence of pollutants disposal in Qarraoun Lake. PCA was used to identify a reduced number of four principal components, which demonstrated 67.46 % of both temporal and spatial changes. CA shows that the Lake is divided into four clusters, where the central represent the most favorable one. Pollution index was used to classify the level of pollution of different sites in the Lake

Metal concentrations in river water and bed sediments of the Lower Litani River Bassin, Lebanon

The distribution of pollutants in the Litani River is almost severe. It resulted from domestic, sewage, agricultural and industrial sources. In this study, the distribution of metals (Cu, Fe, Cd, Mg, Zn, Pb , Al, Ba, Ni, Mn, Ag and Cr) were measured in river water and the bed sediments of the Lower Litani River Basin (LLRB). The impacts of metals on the water quality were monitored during the rainy, mid rainy and dry season in the year 2012. The objectives of this study were first to identify possible sources of metals (i.e. geological and/or anthropogenic) and then to characterize the chemical behavior of these metals in water and bed sediments. Water and bed load sediments were sampled at six sites along the LLRB main watercourse, The metal concentrations in the river sediments were remarkably high, but varied between different sampling sites, and the concentrations in water were mainly within the permissible limits. The metal contents in bed sediment were highest during closure of summer period. By applying the principal component analysis applied to total and extractable metal contents as a tool for studying metal pollution in the LLRB, it was useful to distinguish between anthropogenic and natural sources

Physiochemical and Microbial Assessment of Water Quality in the Upper Litani River Basin, Lebanon

Water resources in Lebanon are witnessing serious challenges and reached depletion. One of the major challenges is the quality deterioration, which is accompanied with uncontrolled resources management, and thus the increasing demand. There are several consumption aspects, mainly the domestic, industrial and irrigation. Yet, exploitation of water resources in Lebanon implies both the surface and groundwater. However, surface water resources are most used due to the ease of exploitation processes, and more certainly water from rivers. Typically, the Litani River is the largest one in Lebanon. The river has been lately subjected to several aspects of deterioration in its quality. This includes the major physiochemical characteristics. This study aims to assess the seasonal variations in water quality in the Upper Litani River Basin, including the Qaraaoun Lake. Samples were collected from particular sites along the river, and at several dates during the years of 2010 and 2011. The carried analysis implies the physical (pH, T°, TDS, Ec), chemicals (Na+, Ca2+, Mg2+, Cl?, SO42?, NH3+, NO3?, PO42?, K+, BOD5 and COD, Heavy metals (Fe, Ni, Zn, Cu, Cr, Al, Ba, Pb, Mn) and microbiological parameters. This resulted numeric data are being compared with WHO guidelines. In addition, PCA was applied to evaluate the data accuracy. We can conclude that the variables used are very efficient and the dry season shows the worst water quality with nitrate, metal and microbial enrichments. Keywords: Water Contamination, Human Interference, Litani River, Principal Component Analysis

Evaluation of the Physicochemical Characteristics of Water in the Lower Litani Basin, Lebanon

International audienceThe physicochemical characteristics of water in the Lower Litani River Basin (LLRB) were evaluated. It concerns with analyzing six representatives sites which are investigated over three seasons of the year 2011. The principal component analysis (PCA) method was used to interpret the elemental concentrations in the river water. Many variables were evaluated, especially the components or metals Fe, NO2-, CaCO3, Cu. Three groups were identified and differentiated by PCA according to the seasons. The first group is rich in Fe and NO2, and low in NH4 and EC (in the mid rainy season). The second group formed in dry season and the third group with low concentration of K+, PO43- and Cl- (in mid rainy). However, no critical pollution has been reported in this part of the river; except the high concentration of Fe and NO2 - in all investigated sites due to the reject of wastewater and touristic activities

Assessment of the physicochemical and microbiological water quality of Al-Zahrani River Basin, Lebanon

International audienceLebanon is a mountainous country with an area of 10452 km2, and it is characterized by a Mediterranean climate having avariable rainfall rate from which a significant amount is manifested as snow. The dense population of Lebanese is locatedin the coastal zone creating a strong anthropic pressure on the water resources. The civil war (1975-1990) and the post-warperiod (1990-2000) have led to a shortage in Lebanese watersheds data due to discontinuation of regular measurements.This study aims at investigating the hydrological response of the Al-Zahrani River Basin by tackling various physicochemicaland microbiological parameters that are related to human activities’ influence on the water quality in six selection sites. Thewater tested physiochemical parameters of the basic temperature (T), the potential of hydrogen (pH), electrical conductivity(EC) and total dissolved solids (TDS), the anions (NO3 - , SO4 2- and PO4 3-), the cations (Na+ , K+ , Ca2+, and Mg2+), and the heavymetals (Cd, Cr, Fe, Cu and Zn). The microbial parameters are Salmonella, Escherichia coli, Total Coliforms, Clostridiumperfringens and Staphylococcus aureus. Furthermore, the most polluted site was assessed through conduction of principalcomponent analysis (PCA) statistics. Microbiological pollution was found at a high level in all sites with a total absence of heavy metals contamination. High nitrate levels were observable in two sites (WadiAkhdar 2 and Zahrani), in addition to a high potassium rate in NabehKfarwah. The PCA assessment highlighted the Zahrani site as the most polluted. The main pollution causes are correlated with wastewaterdischarges and industrial activities

The Distribution of Heavy Metals in the Lower River Basin, Lebanon

AbstractThe distributions of heavy metals were measured in the bed sediments of the Lower Litani River Basin (LLRB). The main objectives of this study were to identify possible sources of metals (i.e. geological and/or anthropogenic) and then to investigate the effect of the seasonal variations in content of metals in the bed sediments. The heavy metal concentrations in the river sediments were remarkably high according to the permissible limits. The metal contents in bed sediment were highest during dry seasons. This was accomplished by applying the correlation coefficient analysis applied to total heavy metal contents as a tool for studying metal pollution in the LLRB and their origins. It was useful to distinguish between anthropogenic and natural sources

Assessing Contamination Level of Heavy Metals in the Lake of Qaraaoun. Lebanon

AbstractWater pollution in the Lake of Qaraaoun became a common criterion and it has been exaggerated in the last few decades as a result of population growth and the changing climatic conditions. The Qaraaoun Lake is the largest artificial reservoir in Lebanon, which is located along the Litani River. It represents the connecting point between the Upper and Lower Litani River Basins. The study aimed at assessing the levels of heavy metals concentration of and their sources in the sediment of the Qaraaoun Lake at three representative sites during dry season of the year 2012