Greywater reuse experience in Sharjah, United Arab Emirates: feasibility, challenges and opportunities

In 2003, the Sharjah Electricity & Water Authority (SEWA) initiated a program mandating installation of greywater reuse (GWR) systems in large buildings in Sharjah to reduce demand for desalinated water. In this article, an assessment of the main challenges and opportunities experienced during implementation of the program is presented. Furthermore, the feasibility of GWR in Sharjah is analyzed for new and retrofitted multistorey buildings, hotels, schools and houses of worship. GWR for toilet flushing in Sharjah buildings proved financially beneficial to tenants on the account of owners, while GWR as makeup water in open HVAC cooling towers proved attractive to owners but not tenants. The lack of financial incentives to owners who were set to lose resulted in significant resistance to the program. Furthermore, insufficient planning prior to launching the program and inadequate coordination and follow up resulted in faulty installations, malfunctions and abandoned systems. As a result, SEWA changed the mandatory GWR requirements to optional in 2014 except for buildings with HVAC cooling towers. Overall, the number of GWR systems in Sharjah remained limited to about 200 installations serving a small fraction of the buildings stock in the city. Therefore, ample potential exists for increasing participation through a modified GWR policy that offers incentives and avoids the shortcomings identified during program implementation. The assessment presented in this study should provide valuable information to stakeholders involved in GWR programs, especially those involved in making decisions and formulating policies in developing countries.