Monitoring and Impact Assessment of Combined Sewer Overflows (MIA-CSO)

Development of a management tool with regard to the conceptual and investment planning of the Berlin combined sewer system

Among urban discharges the impact from combined sewer overflows (CSO) on surface waters plays a prominent role (long term accumulation of nutrients, suspended solids or toxic substances and especially short term aesthetic, toxic and hygienic impacts). MIA-CSO will provide a better process understanding of the impact of CSO on stagnant lowland rivers. The project is based on the experiences gained during the projects SAM-CSO and MONITOR-1.

The overall objective of MIA-CSO is to develop a model-based planning instrument for impact based CSO control. This tool is based on:

  • Data from two years integrated monitoring carried out in river Spree and in the Berlin sewer system at one important CSO. Online sensors will be used in order to gain continuous information on flows and water quality. This monitoring will be the basis for process understanding as well as model adaptation, calibration and validation.
  • Development of a methodology for the assessment of CSO impacts on the receiving water
  • A module for statistical analysis of simulation results for evaluation of management strategies
  • Application of the OpenMI for linking the submodels for sewer system and river water quality as well as the module for statistical analysis

The planning instrument for impact based CSO control will be demonstrated within a case study on an inner city stretch of the Berlin river Spree and will then be transferred for conceptual and investment planning of the Berlin combined sewer system.


Selected publications produced in the MIA-CSO project are available here .


More information

  • Impacts of Combined Sewer Overflows on Urban Waters: Challenges and Solutions for European Citi...

    6 November 2013

    Final Workshop of KWB Project MIA-CSO at the International Water Week in Amsterdam Urban surface waters play an important role for the diversity of a city, the recreation of its citizens, the urban microclimate and in some cases also for drinking water quality. However, urban lake and river ecosystems are exposed to various stressors – among them combined sewer overflows (CSO) – whose…

  • Combined Sewer Management and Water Resources Protection – Measures, Concepts and Researc...

    29 March 2011

  • Integriertes Monitoring von Mischwassereinleitungen in die Berliner Stadtspree – Start de...

    20 April 2010

    Kick-off event of project MIA-CSO on 20 April 2010 Venue: Cast Collection of Ancient Sculpture, Berlin-Charlottenburg During heavy storm events, a mixture of rainwater and wastewater, so-called combined water, is discharged from approx. 100 points of Berlin’s sewer system directly into the surface water. Despite numerous expensive retention measures which have either been implemented already…