Human and organic kitchen waste is collected for processing. Rain water, as well as water from showers and hand basins, is collected to be used in crop irrigation.
Liquid waste is separated from solid waste to allow for it to be treated in different ways.
Solid waste is processed to capture biogas, which can be used to generate heat and power - or as a transport fuel. The treatment material (digestate) can be used as fertilizer and soil conditioner.
Constructed wetlands and maturation ponds are natural solutions to treat wastewater. The techniques use either plants and algae, or fish respectively to break down organic matter and reduce the high levels of nitrogen.
Fertiliser and treated water can be used as effective and natural inputs for organic farming, creating a virtuous circle. Urban agriculture projects reduce the need for transport and offer opportunities to make cities more self-sufficient.