Public Health Quality of Drinking Water supply in Orangi Town, Karachi, Pakistan

Water scarcity is a serious problem in the mega city Karachi. The problem is more pronounced in the slum areas of the city having poor infrastructure and limited facilities. This study presents a quality assessment of piped water supply in the biggest slum area of Asia; the Orangi town. Forty six samples of piped water were collected from different places and examined for bacteriological and physico-chemical analyses as per methods described in the Standard Methods for the Examination of Water and Wastewater. Environmental health quality of piped water supply is found to be unsuitable for human consumption. Physico-chemical characteristics were well within limits except sulphates as per WHO guidelines and National Standard for Drinking Water Quality, Government of Pakistan (NSDWQ). Chlorine was found only in nine samples which reflect the presence of organisms of public health importance. Most critical were the high levels of total coliforms count (TCC) as total fecal coliform counts (TFC), which were present in a very high numbers as compared to WHO guidelines. The presence of high TCC and TFC count represents poor hygienic and sanitation conditions of the area. The field surveys indicated that water supply system is obsolete that need immediate replacement. The study stresses the need for significant improvements of water supply and sewage infrastructure.