Data-driven urban drainage analysis: An alternative to hydrodynamic models?

In the past, there has been an emphasis on the use of hydrodynamic models as a tool for urban drainage analysis. Limited availability of monitoring data and the perceived more limited resource requirements of models led to a preference for this approach. The last decade has seen a gradual development of water quantity and quality monitoring systems through the development of reliable and increasingly cost-efficient water level sensors, continuous water quality sensors and data communication and storage. Employment of monitoring systems has become feasible in a growing number of research and practical applications. Thus, a datadriven approach to system analysis, purely based on monitoring data, has presented itself as a viable alternative to model simulations. The advantage of monitoring data is that they provide direct information on parameters of interest, such as flooded locations, flood depths and combined sewer overflow concentrations, at a level of accuracy that simulation models are unable to achieve. This paper compares urban drainage analysis, for two complexity levels, based on model simulations and on monitoring data. The results show that, given the current state of technology and model instruments, monitoring systems are the most promising way to obtain reliable estimates of crucial urban drainage parameters