A case independent approach on the impact of climate change effects on combined sewer system performance

M. Kleidorfer, M. Möderl, Robert Sitzenfrei, C. Urich, Wolfgang Rauch

Research output: Contribution to journalArticleResearchpeer-review

39 Citations (Scopus)


Design and construction of urban drainage systems has to be done in a predictive way, as the average lifespan of such investments is several decades. The design engineer has to predict many influencing factors and scenarios for future development of a system (e.g. change in land use, population, water consumption and infiltration measures). Furthermore, climate change can cause increased rain intensities which leads to an additional impact on drainage systems. In this paper we compare the behaviour of different performance indicators of combined sewer systems when taking into account long-term environmental change effects (change in rainfall characteristics, change in impervious area and change in dry weather flow). By using 250 virtual case studies this approach is - in principle - a Monte Carlo Simulation in which not only parameter values are varied but the entire system structure and layout is changed in each run. Hence, results are more general and case-independent. For example the consideration of an increase of rainfall intensities by 20% has the same effect as an increase of impervious area of +40%. Such an increase of rainfall intensities could be compensated by infiltration measures in current systems which lead to a reduction of impervious area by 30%.

Original languageEnglish
Pages (from-to)1555-1564
Number of pages10
JournalWater Science and Technology
Issue number6
Publication statusPublished - 2009
Externally publishedYes


  • Climate change
  • Combined sewer system
  • Land use
  • Modelling
  • Performance indicator
  • Rainfall intensities
  • Uncertainties
  • Urban drainage

Cite this