From voluntary adoption to mandatory greywater reuse: a goal-programming policy framework for the United Arab Emirates

Purpose The United Arab Emirates (UAE) meets most of its municipal water demand from energy-intensive water desalination, while greywater is largely discharged to sewage as a waste water. Thus, this viewpoint raises a question about why in-building reuse requirements that already exist in several emirates have underperformed, and proposes goal programming for setting development-specific reuse thresholds to be enforced at the building completion stage. Design/methodology/approach This is a conceptual viewpoint article as it reviews each emirate's jurisdiction requirements, distinguishes the in-building greywater from centralized wastewater treatment effluents and specifies a goal programming formulation with decision variables, goal functions, deviation variables, priority weights and constraints which is represented arithmetically for a hypothetical development. Therefore, no optimization was solved, and no empirical validation was undertaken. Findings Mandates already exist in Dubai, Sharjah and Abu Dhabi. However, it imposes uniform requirements that are not calibrated to population density, land-use mix or end-user demand. Attaching a modelled, specific for a development threshold to the building completion certificate would give regulators an auditable number and master developers a predictable one. Research limitations/implications Priority weights are normative choices, and outputs depend on the local demand and cost data that remain sparse. The framework requires calibration and pilot testing, and public perception of indoor reuse remains a limitation. Originality/value The contribution of this viewpoint is to integrate goal programming with the completion certificate as a calibration and verification mechanism for greywater reuse in arid, rapidly urbanizing Gulf Cooperation Council (GCC) economies generally and the UAE specifically.