
Domestic wastewater contains resources, such as nutrients, water, organic matter which can be reused in agriculture. Nitrogen (N) and phosphorus (P) are two essential macronutrients for crop production. The reuse of recovered products containing these nutrients can contribute to lowered use of fossil energy and saves P reserves. This reuse enhances economic circularity of cities, urban areas or small islands. A number of sanitation planning approaches have been developed aiming to solve the aforementioned problems. However, some challenges on planning have not been addressed in a holistic way when considering the full train of sanitation technologies and is not better integrated with agricultural systems. The assessments are also not considering the four domains of sustainability: environmental, technological, social-economic, and economic, and also trends of future development. Hence, a new planning approach needs to be developed to promote resource recovery and reuse under different future developments.