Keywords: kinematic hydrology, stormwater modelling, urban drainage, runoff, road surfaces, small urban catchments, historical pollutographs, simulation, water pollution, Australia, water sensitive urban design, WSUD, water quality
An alternative approach to modelling stormwater runoff from small urban catchments
The inability of current stormwater quality models to reproduce historical pollutographs accurately and reliably has prompted the need to introduce alternative approaches to simulate stormwater runoff from urban catchments. In view of the increasing popularity of designing urban stormwater systems using the Water Sensitive Urban Design (WSUD) approach, it is also essential to adopt a modelling approach that enables differentiation between the various sources of pollutants such as roofs, roads and other impervious surfaces. Using data from small urban catchments in Sydney, this research attempts to improve the accuracy of stormwater runoff predictions by adopting a more process-based approach. This resulting runoff model will be enhanced to simulate stormwater runoff quality, subsequently serving as an important tool in urban catchment management studies. Other findings from the modelling exercise include the necessity of adopting a finer resolution for the recording of rainfall and the inferiority of the plane and gutter approach compared to a simplified diagonal approach in conceptualising the catchment.