General Sewage Technology

Water system for rainwater use and wastewater purification

The innovative water infrastructure system developed by the project facilitates use of rainwater and purification of municipal wastewater. The collected wastewater flows are treated using state-of-the-art membrane technology and redistributed according to water quality. In addition, the system achieves recuperation of usable substances contained in the wastewater and reduces consumption of potable water in households.


In the conventional water system, make-up water is treated and supplied to consumers at drinking water quality. The produced wastewater is channelled off together with the rainwater and then, following purification, introduced to surface water bodies. Problematic here, is the relatively high pollution of water bodies through untreated wastewater as well as sludge recycling due to the pollution of the effluent sludges, e.g. through heavy metals introduced by industrial sites. Furthermore, the various usages (e.g. toilet water, process water) are all supplied with drinking water quality even though the share of usages with maximum quality requirements (food, drinking) is very low. 

As part of the project, an innovative water infrastructure system was therefore to be developed and tested. The novel approach of semi-decentralised rainwater use and purification of municipal wastewater is intended to use wastewater-borne substances as a material resource and energy source while reducing the amount of central system components.


  • Rainwater treatment is performed via a membrane pretreatment and disinfection stage and produces high-quality utility water which, in terms of hygiene, corresponds to drinking water quality.
  • The untreated water is then used as its quality allows. Redistribution to the buildings then occurs via a separate network.
  • Untreated wastewater is collected via a vacuum system and treated as highly concentrated, solids-bearing wastewater with the aim of obtaining materials and producing energy.
  • A settlement's roadwater and surface water are collected separately, purified and stored in a fire-fighting reservoir or retention channel. Alternatively, they can be treated for use as process water.
  • The surface rainwater and excess purified wastewater filtrates are channelled to ponds within the built-up area. The purification methods used guarantee that the ponds' water quality is very high, substantially exceeding the requirements of the EU Bathing Water Directive.

More Project Informations

Project title:  Dezentrales Urbanes Infrastruktursystem DEUS

Project number:  02WD0457

Project period:  2003 - 2008

Project region:  Germany (Bavaria)

Project contact:

Herr Dr.-Ing Mohr

+49 (0)711 970-4216

+49 (0)711 970-4200

View Publication

Source: German National Library of Science and Technology Hannover (TIB)