Calibration and Sensitivity Analysis of Urban Drainage Models: Music Rainfall/Runoff Module and a Simple Stormwater Quality Model

Abstract

Model calibration and sensitivity analysis of stormwater models are required to assess model performance; it is very unlikely that non-calibrated models will lead to reasonable results. The aim of this paper is to present results of the calibration and sensitivity analysis of the key parameters used in flow modelling by MUSIC and parameters of a simple stormwater quality model. The assessment of the models is undertaken using a Monte Carlo Markov Chain approach. We describe the models’ performance, provide information on their sensitivity to parameters and also discuss the correlation between these parameters. This work will help practitioners to understand importance of the MUSIC parameters that they usually use without calibration. The information reported in the results will also help to guide future development of stormwater quality models and the data needed to support it.

Key Words:

• MUSIC rainfall/runoff module
• water quality model
• calibration
• sensitivity analysis
• Monte Carlo Markov Chain methods

Additional information

Notes on contributors

C B S Dotto

Cintia Dotto graduated in Civil Engineering in Brazil. Upon graduation, she spent some time working for an environmental consultancy company until she went back to academia. She then completed her Masters degree in Civil and Environmental Engineering, where she became involved in urban water research. Cintia joined Monash University in 2006 as a PhD student and she is currently working on the final stages of her research.

A Deletic

Ana Deletic is a Professor in Water Engineering within Monash University’s Civil Engineering Department, and Director of the Centre for Water Sensitive Cities, an interdisciplinary research centre involving 50 researchers at Monash University. Biofiltration developed under her leadership was implemented across Australia and exported to Singapore and Israel. She led development of MUSIC V4, the industry-recognised tool for design of WSUD systems. She co-leads Australian involvement in a $10 million EU FP7 project PREPARED, that aims to adapt urban water systems to climate change. She is chair of International Working Group on Data and Models that works under Joint Committee on Urban Drainage (IWA/IAHR). Ana is a Fellow of Engineers Australia. She won the 2008 Dean’s Award for Excellence in Engineering Research.

D T McCarthy

David McCarthy’s research interests include improving monitoring regimes for urban stormwater systems; novel modular porous pavement systems designed for reuse applications; modelling of urban stormwater quantity and quality (mostly microorganisms); quantifying model uncertainty; development and design of stormwater harvesting systems; and characterising the microbial quality of both wet and dry weather stormwater flows. After submitting his PhD thesis in July 2008, he was employed as a Research Fellow at Monash University, where he played an integral part in the success of an internationally-recognised research team. He has recently been offered a lecturer position in the Civil Engineering Department (2010).

T D Fletcher

Tim Fletcher is internationally regarded for his expertise in stormwater quality, treatment and impacts, having written 200 publications on the topic. His research focus has included modelling stormwater flows, quality and the performance of stormwater treatment systems, and ecosystem response to stormwater management. Tim is now leading a research collaboration with INSA Lyon (France) through the Australian Government DEST International Science Linkages Program, on a project titled “Coping with Uncertainty in Stormwater Models”. He is also leading, with A/Prof Walsh, a project retrofitting a small urban catchment with rainwater tanks and biofiltration systems, in order to assess the impact on the receiving stream.