An Investigation into the Urban Water Cycle in the City of Dubai, United Arab Emirates Karkain Rashed*, El Sergany Moetaz**, Diamadopoulos Evan*** *Dubai, UAE **Dubai Academic City ***School of Environmental Engineering, Technical University of Crete, Greece Online published on 22 April, 2019. Abstract The aim of this study is to assess the water cycle in the City of Dubai from water supply through all stages till disposal or reuse. The results obtained revealed that there is a deficit of about 44% between the amount of water supply and the wastewater generated. In 2016, the total amount of wastewater generated was found to be 680,000 m3/d, exceeding the overall capacity of the existing wastewater treatment plants by 20.3%. The quality of inflow to wastewater treatment plants revealed to have high amounts of sulfates (SO4), Biological Oxygen Demand (BOD5) and ammonia nitrogen (NH4-N) with a noticeable content of Chemical Oxygen Demand (COD). Analysis of treated sewage effluent (TSE) revealed that ammonia (NH3), silver (Ag) and sodium (Na) exceeded the restricted irrigation standards, and as per Dubai Government's Administrative Order No 30/2008. Nickel (Ni) and lead (Pb) were found at alarming levels, although their values were below the local standards. Total Coliform contamination in TSE was in the range of 459–43321 MPN/100 ml, E.Coli levels were in the range 0.93–4047 MPN/100 ml, while Enterococcus was measured in the range of 2.37–8240 MPN/100 ml. The E.Coli level frequently exceeded the limit of <100 MPN/100 ml. Top Keywords Treated Sewage Effluent, Urban Water Cycle, Wastewater management. Top |