Integrated urban drainage uncertaintyassessment : the influence of the likelihoodefficiency measures

The uncertainty analysis of a home-made integrated urban drainage model is presented. The model is able to estimate both the interactions between sewers system, WWTP, CSO and RWB and the modifications, in terms of quality, that urban storm water causes inside the receiving water body. The uncertainty has been worked out by mean of the GLUE methodology which relies on some user-defined hypothesis; one of these is the adoption of the Nash-Sutcliffe equation to evaluate the likelihood parameter distributions. To understand the influence of the efficiency equation, several modelling efficiency expressions were considered and the correspondent uncertainty was evaluated. The model was applied to the Savena case study (Bologna, IT) where both quantity and quality data during dry and wet weather period were available. The results are interesting and show a strongly influence of the GLUE methodology by the efficiency measure.

[1]  J. Nash,et al.  River flow forecasting through conceptual models part I — A discussion of principles☆ , 1970 .

[2]  G Mannina,et al.  Integrated urban water modelling with uncertainty analysis. , 2006, Water science and technology : a journal of the International Association on Water Pollution Research.

[3]  Keith Beven,et al.  The future of distributed models: model calibration and uncertainty prediction. , 1992 .

[4]  Poul Harremoës,et al.  The importance of the treatment plant performance during rain to acute water pollution , 1996 .

[5]  K. Beven,et al.  Bayesian Estimation of Uncertainty in Runoff Prediction and the Value of Data: An Application of the GLUE Approach , 1996 .

[6]  H. Christopher Frey,et al.  Quantitative Analysis of Uncertainty and Variability in Environmental Policy Making , 1992 .

[7]  M. B. Beck,et al.  Water quality modeling: A review of the analysis of uncertainty , 1987 .

[8]  Marco Maglionico,et al.  Water Quality Modelling in Ephemeral Streams Receiving Urban Flows , 2000 .

[9]  P. Mantovan,et al.  Hydrological forecasting uncertainty assessment: Incoherence of the GLUE methodology , 2006 .

[10]  Keith Beven,et al.  Equifinality, data assimilation, and uncertainty estimation in mechanistic modelling of complex environmental systems using the GLUE methodology , 2001 .

[11]  P. Willems,et al.  Sensitivity and uncertainty analysis for river quality modelling , 2004 .

[12]  P. Willems.  Probabilistic immission modelling of receiving surface waters , 2000 .