A life cycle assessment of a mini urban water system : a campus case study

With two thirds of the earth's surface covered by water, it is evidently clear that wateris one of the prime elements responsible for life on earth. Water circulates through theland, transporting, dissolving and replenishing nutrients and organic matter, whilecarrying away waste material. Urban water systems are essential for the supply ofsafe drinking water and waste disposal, and also through the amenity and ecologicalroles of water. Significant resources are invested to ensure that complex urban watersystems meet the levels of service and performance requirements defined byincreasingly stringent legislation, whilst minimising financial, environmental and socialcosts. The situation becomes multi-faceted especially for developing countries, wherethe urban water system has additional difficulties in meeting the challenge of anincreasing population and the demand for less capital intensive solutions.The main theme of the research is to assess water systems and their management on theObafemi Awolowo University campus (a mini-urban centre) Ile-Ife, set in South-WesternNigeria with a population of over 20,000 students and various physical facilities. Theobjectives are to determine environmental, financial and social impacts originating fromthe present water system management, identify ""hotspots"" within the water systemwhere impacts are significant and to improve water service delivery by recommendingmitigation options. The focus was on four subsystems that constitute the university's watersystem: water treatment, water distribution, water use and wastewater treatment.A life cycle-based methodology was used to assess the university's water system in thethree domains of sustainability i.e. the environment, economy and society. Henceenvironmental, financial and social life cycle assessments were undertaken.The environmental impact of the OAU UWS (from water abstraction/treatment towastewater treatment) was found to be 0.408 Eco-points/m3 of treated water. Withthe implementation of the recommended mitigation options, this can be decreased to0.287 Eco-points/m3, a 30% reduction. In financial terms, the present management ofthe OAU UWS costs €7.36/m3 from water treatment to wastewater treatment. A 39%reduction is possible when the system is improved resulting to €4.46/m3. Social impactsof the OAU water treatment, water distribution, water use and wastewater treatmentsubsystems were -133, -201, -137 and -183 Socio-points/person/years, in that order.An improved system will ensure increases to 93, 164, 137 and 195 Sociopoints/person/year with respect to the four subsystems. The use of Aluminium Sulphateas a coagulant in water treatment, distribution via water tankers and use of kerosene(for cooking) and organic disinfectants (for bathing) all contribute significantly to bothenvironmental and financial impacts within the OAU UWS.It was found that environmental and financial impacts are interconnected andcorrelated, with the financial aspect dependent on the environmental feature. Areduction in environmental impacts (ensured by a better managed and integratedwater system) will always result in corresponding decrease in financial costs, on the longrun. In more general terms, it was found that poor operation/maintenance appears tolead to savings but results in more environmental costs and on the long run morefinancial costs and ""unhappy"" workers and water users. Short-term profit will alwaysbring about long-term losses