One of the largest urban development projects at present in Hamburg is the conversion of former military barracks into a new residential area for about 630 households, called Jenfelder Au. The urban design concept for this 35 ha area follows a high quality approach to develop a carbon-neutral, attractive neighbourhood for approx. 2,000 inhabitants abundant with green space and urban water. HAMBURG WASSER, Hamburg's water supply and wastewater utility, is rethinking the way of wastewater management by implementing an integrated concept for decentralised wastewater treatment and energy production – the so-called HAMBURG WATER Cycle® (HWC) – in this new residential area, based on source control of wastewater. Stormwater, greywater and blackwater are collected separately and then treated separately on site in Jenfelder Au. The realisation of the HWC will be the hitherto largest demonstration of a resource oriented sanitation concept working with vacuum technology for the collection of concentrated blackwater. This concept intends to establish synergy between wastewater management, waste management and energy production, and contributes to an improved local natural water cycle.