Why? – Project Goals
Urban water and wastewater management needs to be deeply transformed, away from end-of-pipe to circular designs. Actors around the world have started developing decentralised urban water treatment and reuse systems (DUWTRS). DUWTRS locally treat and recycle water and the resources it contains (heat, energy, nutrients) in closed-loop systems. They increasingly include source-separation, i.e. divide various ‘waste flows’ such as greywater, blackwater, rainwater or kitchen waste and convey them to separate treatment processes (cf. Figure 1). This promises efficient treatment and targeted resource recovery.
Yet, in solving multiple challenges at once, DUWTRS typically transcend traditional institutional and regulative boundaries between the waste, water and energy sectors, as well as between the public and private sphere. In effect, only a few cities worldwide have successfully implemented innovative approaches at scale. We lack well-documented templates and best practices that inspire and inform on how to best implement DUWTRS. Thus, the Lighthouse Project (LH) assessed key case studies, which could serve as ‘templates’ that inspire other cities around the world.