Physicochemical and Microbiological Water Quality of PWD, Gulberg and Korang River, Islamabad, Pakistan

Water Quality, Assessment, Islamabad

Abstract

This study evaluated the physicochemical and microbiological quality of water from PWD Colony, Gulberg Green and the Korang River (n = 36 samples, April–May) to determine suitability for domestic use and public-health risk. Samples were analyzed for pH, temperature, electrical conductivity, total dissolved solids, turbidity, alkalinity, hardness, chloride, fluoride, arsenic, total bacterial count and indicator/pathogenic bacteria (Escherichia coli, fecal coliforms, Salmonella, Shigella). Results showed variable water quality across sites: pH ranged 5.8–8.5 (mean = 7.4), TDS 230–858 mg/L (mean = 544 mg/L) with elevated EC/TDS in Korang samples, extremely high turbidity in Korang River samples (92–201 NTU), fluoride up to 3.4 mg/L (exceeding WHO guideline of 1.5 mg/L) and arsenic peaking at 0.10 mg/L (100 µg/L, far above the WHO limit of 10 µg/L); microbiological contamination was widespread with frequent detection of fecal indicators and pathogenic genera, in several cases at counts reported as “too numerous to count,” indicating fecal intrusion and sanitary failures. On the basis of comparisons with WHO/national standards, the Korang River exhibited the poorest physicochemical quality while PWD and Gulberg point sources often suffered microbiological contamination; the findings call for source protection, repair and monitoring of distribution systems, targeted treatment (e.g., turbidity control, defluoridation/arsenic mitigation) and routine microbial surveillance to reduce waterborne disease risk in the study area.