Urban hydrology is a new domain of expertise at VITO. The tool developed in the frame of the PhD of E. Salvadore is one of the hydrological models which we can be applied to calculate run off, recharge and flooding risks in larger urban areas for example Chinese mega cities. The model is also the base for a specific application in which we are able to calculate the amount of used pesticides running of impervious surfaces, allowing to estimate the effects of these chemicals on surface waters.
PhD Salvadore Elga: “Development of a flexible process-based spatially-distributed hydrological model for urban catchments”
Growing population and urbanization augment the pressure on the environment and water resources sustainability. Urban environments are highly heterogeneous and multiple processes take place at various spatial and temporal scales, making the hydrological modeling of urban water system highly complex. The PhD of Elga Salvadore aims at providing more insights in the urban hydrology field by developing an innovative integrated system for the hydrological analysis of urban catchments: the spatially-distributed WetSpa-Python model and its extensions (Water and Energy Transfer between Soil, Plants and Atmosphere based on Python).
The first part of the thesis provides an in-depth analysis of the current literature on urban hydrological modeling and proposes a blueprint for future developments in the field (Salvadore et al., 2015a). The second part of the thesis deals with the development and the validation of the WetSpa-Python model (Salvadore et al., 2015b). The WetSpa-Python model is the Python reimplementation of the spatially-distributed hydrological model WetSpa. In this reimplementation, every semi physically-based process is coded in a separate module and modules exchange data during run time through a Python modeling framework. The model builder can select which processes will be simulated and the spatial and temporal resolution of each module separately. The model structure can therefore be easily modified according to the case study requirements. A series of theoretical and real-case examples demonstrate the flexibility of the newly developed tool and its wide range of applicability. The last part of the work deals with the development of urban-specific extension for the model for (a) improving the groundwater flow simulations, (b) including the effects of dynamic land use change, and (c) simulating storm drainage flow. The combination of these three extensions with the WetSpa-Python model can be used to simulate various urban-related impacts on the water system.
The main advantage of the WetSpa-Python approach in the enhanced flexibility. An ensemble of models with different structures can easily be generated to study a particular catchment and calibration can be performed not just on parameters but also on hydrological processes.
Salvadore, E., Bronders, J., and Batelaan, O., 2015a. Hydrological modeling of urbanized catchments: A review and future directions. Journal of Hydrology, 529(1), 62-81.
Salvadore, E., Bronders, J., Schmitz, O., van der Kwast, J., and Batelaan, O., 2015. Flexible process-based hydrological modelling: the WetSpa-Python model. Journal of Environmental Modelling & Software, under review.