Guideline DWA-M 277E Information on design of systems for the treatment and reuse of greywater and separated greywater flows

The urban water management must address new challenges. Examples include the impact of demographic trends and climate changes or the implementation of resource protection measures. New Alternative Sanitation Systems (NASS) represent one potential approach, where technologies are used to close as far as possible the water and material cycles for the purpose of recycling the valuable components present in wastewater. The planning and implementation of NASS principles are described in the Standard DWA-A 272. An integral part of NASS according to Standard DWA-A 272 is the treatment and reuse of greywater. Following numerous research projects and long-term scientific studies, greywater reuse systems produced industrially for the treatment of separated greywater flows within the building services engineering are available on the market. However, to date there exist no technical regulations for these systems. The Guideline DWA-M 277 can be applied to systems which process and supply service water from greywater for private as well as public/commercial buildings, or which treat the greywater and discharge it. These include, inter alia, single- and two-family houses, multi-family houses and large residential complexes, administrative and training institutions. Moreover, this document can also be applied to systems in the commercial sector such as in hotels, guest houses, sports facilities, camping sites and restaurants. The present Guideline provides information and assistance for the planning, design, construction, operation and maintenance of greywater treatment and reuse systems for different applications. Systems, which do not treat the generated greywater, are not covered by this document.