“The detection of leaks and bursts in water distribution systems represents a compelling and critical issue in water conservation world-wide.” This is the view of international water expert, Prof Ezio Todini, who spoke at the Tshwane University of Technology’s 25th VC’s Research and Innovation Seminar. The theme of his talk was about a water distribution modelling under an uncertainty perspective.
In his opening remarks, Prof Lourens van Staden, TUT Vice-Chancellor and Principal said the loss of treated, and frequently pumped water, is not only a waste of resources, money and energy, it also poses a potential health risk due to the potential of pollution through cracks or openings. “TUT is excited and appreciate Prof Todini sharing his expertise on this topic,” he said.
Prof Todini said using the Bayesian decision approaches was the only way to effectively take educated decisions. These require the assessment of a predictive probability density that encapsulates all the available information. “In contrast, it is common practice to use water distribution network models as deterministic tools by taking decisions based on their outputs, regardless of the actual reliable level of information they can provide,” he explained.
“The outputs of water distribution network models are often affected by other uncertainties present in the modelling,” he said. These could include uncertainty and a lack of observation, uncertainty in the pipe layout as well as in the actual pipe conveyance. “The effects of disregarding these uncertainties on the final decisions have not yet been sufficiently investigated. In the past decades, fast and performing water distribution network models have become easily available and widely used, therefore it is essential to take an alternative “uncertainty based” approach to fully benefit from their potential in decision making,” Prof Todini continued.
In conclusion, Prof Todini emphasised that model simulation should aim at assessing the predictive probability densities of the stated variables (flow in pipes, demand and pressure at nodes), of the parameters (pipe conveyances) and of the leakages, to estimate the expected value of benefits and to maximize them, or of losses and to minimize them, in search of the most advantageous decision.
- Prof Ezio Todini is a retired Professor of Hydrology at the University of Bologna, a position he has held from 1980 to 2010. He is an Honorary President of the Italian Hydrological Society, where he served as Founding President and President since its foundation in 2009. Prior to this, he combined his role as a Research Scientist at the IBM Pisa Scientific Centre (1970-1979) with that of Professor of Applied Hydromechanics at the University of Pisa (1973-1980) and of Water Resources Planning at the University of Florence (1979-1981). His background and experience includes Hydrology, Hydraulics, Statistics, Numerical Methods and Operations Research.