The Water Metabolism Of Residential Buildings In Adama City, Ethiopia

Abstract

Water is the basic metabolic requirements of a city. The fastest population growth and raise per capita income put pressure on the water resource. Within the scarce supply, consumption intensifies the scarcity. The research aims to identify water consumption pattern, recycled water use, and rainwater harvesting potential of residences in the Oromia region Adama city using 203 samples selected by combined stratified and simple random sampling. Resident’s consumption data using interview and meter reading from Adama water supply, sanitation, and sewerage enterprise were used. MS Excel was used to analyze data and plot graphs. The result of the analysis had shown inconsistent supply in which 84% was consumed for hygiene purposes including 33.7% for cloth washing and 24.7% for toilet flushing. Indoor utilities, frequency, and duration of indoor activities, and family size affect consumption volume directly. The consumption trend is linear where the input water expelled without further uses. From 20,199.4m2 sampled residents roof area with 804mm mean annual rainfall potentially 15,428 m3 of rainwater can be harvested that could support the supply. It is concluded that the water management of Adana residents is poor with low environmental consciousness. The largest percentage of potable water is used for non-potable purposes which can be easily compensated by rainwater harvesting and greywater reusing. It is finally recommended to offset the non-potable use of water by harvesting rainwater and aware consumers the importance of roof water harvesting system to be sustainable enough. Tariff adjustment can also be done for those who used rainwater and offset most of their potable water demand from the municipality.