Author(s): Douglas Bertram; James Minto; Heather Haynes; Matthew Roberts
Linked Author(s): Heather Haynes, Douglas Bertram
Keywords: Surface Water Management Model (SWMM); TUFLOW; Integratedurban drainage (IUD); Hydraulic modelling; Sensitivity analysis; Urban flooding
Abstract: Surface Water Management Models (SWMMs) incorporate predictions of surface water flooding, flood routes and quantification of the flood hazards and associated risk in urban environments. This had led to the development of integrated 1D/2D models that dynamically link surface hydraulic models to subsurface models representing local urban drainage infrastructure. Whilst these Integrated Urban Drainage (IUD) models are increasingly employed in flood risk assessment, benchmarking and performance analysis is limited and generally case-study specific. This study therefore investigates how the performance of the link element connecting the surface and subsurface model domains is influenced by model configuration, discretisation and topographic variability. Data was collected using a generic urban street SWMM developed in TUFLOW 2D hydraulic modelling software. Results indicate that model sensitivities were greatest (>30%) for the drainage network infrastructure configuration and for model discretisation resolution of the surface road section model. This was particularly evident at low flow, where the 1D/2D link element cell placement and local elevation variations proved critical to surface water capture by the drainage network. Conversely, the definition of minor topography such as road camber was shown to be least influential on flow capture.
Year: 2009