Physio-chemical and microbial analysis of the Kadisha-Abou Ali river, North Lebanon

Abstract

The usage of surface water for different purposes (potable supply, industry, agriculture, recreation) is increasing, while it is subject to anthropogenic and natural factors that highly affect its quality. These factors remain uncontrollable over time especially in a country like Lebanon where an absence of proper environmental management and lack of financial planning. This study aims to measure the content of physical (temperature, pH, DO, turbidity, TDS, conductivity, salinity), chemical (chloride, nitrite, nitrate, sulfate, phosphate) and microbiological (E. Coli and Total Coliforms) parameters of Abou Ali/Kadisha River located in the Northern region of Lebanon. The study consists of locating reachable points where samples can be taken using GPS, collecting water samples in mid-September (dry season) over 2 consecutive days, generating physical, chemical, and microbiological analysis in the lab using HORIBA multi-parameter apparatus, ion chromatography, and membrane filtration. Results of each parameter are compared to the World Health Organization (WHO) standards and Lebanese Ministry of Environment (MOE) standards, and discussions are held to show the relation between these results and the anthropogenic activities and land use in each location. Results obtained during the dry season which is the most critical, suggest that the river water turbidity and DO percentages are very high (ranges between 13.62 and 17 mg/L), while all other physical and chemical parameters are within the limit recommended by WHO and Lebanese MOE standards, except nitrite which is excessively high (ranging between 28.59 and 612.64 mg/L). The river has also shown to be overly polluted with fecal and total coliforms (ranges between 467 and 74000 CFU/100ml). A full analysis of the overall water quality parameters has suggested that contamination of the river is highly related to anthropogenic activities, mainly solid and sewage waste disposal especially in urbanized and highly populated areas, in addition to runoff from agricultural activities and farms in rural and semi-urban areas.