The document suggests applying the concept of separating grey water and black water in Egypt, starting with new communities and rural areas. Separating grey and black water could help sustain good wastewater management and minimize treatment costs. The document recommends applying this concept in university campuses by reusing grey water for irrigation, which could reduce drinking water consumption. It also suggests applying the concept in tourist resorts and villages. Finally, the document proposes using ecological drains to treat grey water in rural areas and increase septic tank efficiency for black water, providing a sustainable low-cost treatment option for rural sanitation.