Reuse of Greywater and its Role in the Sustainability of Water Resources – A Study in Saudi Arabia

Reuse of greywater has become one of the proposed solutions worldwide to support water resources; that are subject to depletion in desert areas such as Saudi Arabia, where rainfall is scarce, suffering growing water demand for municipal and agricultural purposes, and the sustainability of groundwater resources on the other. In Saudi Arabia greywater represents nearly 55-74% of the water consumed in the buildings; so this study aimed to answer the following question: According to ministerial order No. 228 of 29 August 1426 AH, which stipulates that greywater should be reused and that two wastewater recycling systems should be implemented in the development of specifications and plans for the construction of new installations in the sectors concerned; Are there any indicators which prove the implementation of this ministerial decision? What is the evidence for this application? The reuse of treated greywater depends on the natural, chemical, and physical characteristics of the amount of biological consumption of oxygen (BOD5), total suspended solids (TSS), and the chemical oxygen demand (COD). The study concluded that some of the general natural characteristics of water are similar in value to those of high-income and low-income countries. The results show a continuous increase in water consumed through the study period within the urban and agricultural sectors, of Saudi Arabia into global support for the conservation of natural resources.