American Journal of Water Resources. 2014, 2(5), 110-117DOI:
Abstract: Public water supply is distributed through water pipe network, which may affect the quality of water that gets to the consumers if the integrity of the pipe distribution network is compromised. Hence, this study was designed to determine whether there is significant variation in the water quality that gets to the consumer after transportation through the pipe distribution network. In order to achieve this aim, twenty-five tap water samples were randomly collected. In addition, a control sample was collected from Iju Water Works, which serve Ojota community. The analyses revealed that the measured values of some of the selected tap water quality parameters varied from Iju Water Works, to the various sampled zones. For example, total coliform and fecal coliform bacteria counts show that 8 (30.72%) and 6 (23.08%) samples have concentrations above the WHO zero thresholds for total and fecal coliform, respectively. In addition, turbidity and color show unsatisfactory concentrations in some of the sampled tap water, as turbidity has 17 (65.38%) of the samples having concentration above the 5 NTU WHO threshold for drinking water; while all the 25 (100%) tap water samples, have color values above the WHO 5 unit threshold. Similarly, the values of residual chlorine vary from 0.5 mg/l at Iju Water Works, to 0 – 0.25 mg/l at the various zones. The T-test analyses revealed that there are significant differences between the quality values at Iju Water Works and the various zones. This is an indication that the integrity of the treated water transported to Ojota has been compromised and not safe for human consumption. It is recommended that the Lagos State Government should undertake a general overhaul and replacement of the dilapidated water pipe distribution network in the state to guarantee safe supply of tap water to the populace.