Hira Zeb

In this study, climate change and human impacts on water quality in five major urban areas of Pakistan, including Karachi, Lahore, Peshawar, Abbottabad, and Gilgit, were determined. Secondary data on various physical, chemical, and bacteriological water quality parameters were taken from published papers, reports, and theses. Surface and groundwater were the major sources of drinking water in these cities. The physicochemical parameters were total turbidity, pH, dissolved solids (TDS), sulphates, chlorides, calcium, sodium, HCO₃, potassium, magnesium, nitrates, fluorides, arsenic, and hardness. The bacteriological parameters were total coliform, total faecal coliform, and total plate counts. The data revealed that pH, TDS, fluoride, chloride, HCO₃, sodium, and hardness were above the limits in Karachi. MCB Market, Goth Ibrahim, and Malir Town were the main contaminated areas in Karachi. In Lahore, arsenic was found above the limits in all sampling locations. Turbidity, pH, HCO₃, calcium, magnesium, and hardness were found above the limits in Peshawar. In Gilgit city, all physicochemical parameters were found within the limits except turbidity, which was 10 NTU in Nomal valley. Nitrates were higher in the water sources in Abbottabad. Bacterial contamination was found in the water of all five cities. Most of the studies revealed that this contamination could be human-induced. The improper disposal of solid waste, sewage, and animal waste and the excessive use of fertilisers deteriorate the quality of the water. Precipitation, a rise in temperature, and seasonal variation are climate variables that affect water quality and are responsible for major outbreaks of waterborne diseases. There is an urgent need for regular analysis, proper management, and proper treatment of drinking water before it is supplied to the local community in these cities.