Environmental impact on the bacteriological quality of domestic water supplies in Lagos, Nigeria

Abstract

ObjectiveTo assess the impact of town planning, infrastructure, sanitation and rainfall on the bacteriological quality of domestic water supplies. Methods Water samples obtained from deep and shallow wells, boreholes and public taps were cultured to determine the most probable number of Escherichia coli and total coliform using the multiple tube technique. Presence of enteric pathogens was detected using selective and differential media. Samples were collected during both periods of heavy and low rainfall and from municipalities that are unique with respect to infrastructure planning, town planning and sanitation. Results Contamination of treated and pipe distributed water was related with distance of the collection point from a utility station. Faults in pipelines increased the rate of contamination (p<0.5) and this occurred mostly in densely populated areas with dilapidated infrastructure. Wastewater from drains was the main source of contamination of pipe-borne water. Shallow wells were more contaminated than deep wells and boreholes and contamination was higher during period of heavy rainfall (p<0.05). E. coli and enteric pathogens were isolated from contaminated supplies. Conclusions Poor town planning, dilapidated infrastructure and indiscriminate siting of wells and boreholes contributed to the low bacteriological quality of domestic water supplies. Rainfall accentuated the impact.

Microbiological evaluation of sachet water and street-vended yoghurt and “Zobo” drinks sold in Nsukka metropolis

“…Therefore an adequate supply of clean, wholesome water for domestic consumption must be carefully treated before use so that it is not injurious to health (Egwari and Aboaba, 2002; United States Centers for Disease Control and Prevention, 2006). One means of establishing and assuring the purity and safety of water is to set a standard for various contaminants.…”

Assessment of Borehole Water Quality for Domestic Use in Three Selected Wards in Wudil Local Government Area, Kano State

“…Even if no source of anthropogenic contamination may exist, there is potential for natural levels of metals and other chemicals to be harmful to human health. The natural water analysis for physical and chemical properties including trace element content is very important for public health studies (Egwari & Aboaba, 2002). These studies are also a main part of pollution studies in the environment.…”

Effectiveness of storage as a point-of-use means of improving the bacteriological quality of drinking water

“…However, due to the limited success of these agencies to fulfil their mandate, the public relies solely on private wells, boreholes, stored rain water, water vendors and more recently sachet water for drinking (Egwari and Aboaba, 2002;Dada, 2009). In most Nigerian cities and towns pipeborne water is either non-existent or at best fraught with epileptic supply.…”

“…The (Alabi et al, 1998;Egwari and Aboaba, 2002;Raji and Ibrahim, 2011). The World Health Organization guidelines for bacteriological water quality recommends that all water intended for drinking should contain no coliform organism in any 100 ml sample taken and should be free from all hazardous materials as well as being tasteless (WHO, 1995).…”