With the rapid urbanization and growing population, some of the main issues in sustainable management of wastewater in cities include the protection of water resources, high energy demand in the operation of wastewater treatment facilities and direct disposal of treated effluent/by-products resulting in loss of opportunity to recover nutrients. Urban water and wastewater systems in particular are energy intensive starting from water abstraction to treatment and disposal. In large cities the management of wastewater is becoming quite important due to implications on the productivity of the aquatic environment, including critical water resources, and people's quality of life specially those who are disadvantaged in many countries.

The cities of the future needs to be evolved with integrated planning of wastewater, energy and resource management. Recovery of resources from wastewater would not only supply nutrients (nitrogen and phosphorus) in the form of renewable fertilizer, but also it will reduce the energy demands in the production of fertilizers. Moreover, clean water can be produced which will further reduce pumping energy requirement for water supply in most cases. In particular, the use of recycled phosphorus in urban farming and agriculture in the cities of future would ensure the booming future populations can survive. In view of the booming population and associated nutritional requirements of future generations food production must increase significantly.

This project (NexCities) will lay the groundwork for future research and knowledge application on systematic understanding of complex interrelations within a newly proposed concept of Water - Energy - Nutrient nexus, as a critical subset of broader Energy-Food-Water-Environment Nexus. A participatory stakeholder model based on fuzzy cognitive maps will be adopted to understand broader implication of Water - Energy - Nutrient nexus. This project aims beyond theoretical projections related to wastewater treatment and nutrient recycling, and particularly targets generation of new data by conducting systematic experimental investigation on quantities of nutrient and energy resources and their flows in Metro Manila wastewater.

Potential Impact:
The aim of NexCities project is to establish new research collaboration to address the issues of global importance. NexCities will bring consortium of interdisciplinary and multinational researchers together to address the problems of the cities of future. Through this project the consortium of researchers with a wide range of expertise will identify the critical elements of Energy-Food-Water-Environment Nexus, and will deliver knowledge and information that will have both short and long term impacts on the welfare and well being of general public, and particularly disadvantaged communities.

In short term the organisations such as water utilities in Metro Manila and in the UK will be benefited from the knowledge generated in this project. Also, research organisations, international agencies, Philippines government departments, social groups and policy institutions will be benefited by the outcomes of this project. Considering both energy and fertilizer prices in the Philippines, new knowledge generated in this project will have a long term impact on the local businesses, farmers and social communities.