To address the major aspects in managing stormwater quality, we developed ‘MEDUSA Online: Contaminant Loading On-Demand’. The web portal allows catchment managers to investigate catchment characteristics, quantify loads from individual surfaces, compute in-stream concentrations in the receiving waters, prioritise sub-catchments and simulate mitigation measures to determine the impact of green infrastructure on contaminant loading and concentration.
The system generates predictions of single-rain-event contaminant loads at the point of runoff from individual surfaces. Users can identify the spatial distribution of contaminants as well as the relative contribution from the different surface types in the catchment at both event and annual timeframes. With the simple interface, users can easily explore the effects of implementing different treatment systems (at source as well as end-of-the-pipe) at any site in the catchment.
The solution integrates University of Canterbury’s MEDUSA (Modelled Estimates of Discharges for Urban Stormwater Assessment) engine with MIKE Powered by DHI software MIKE URBAN (now MIKE+). The integrated system estimates the amount of contaminants generated by individual surfaces within the catchment, based on local monitoring of different surface types. Features include the surface-specific load generation component, based on rainfall characteristics and the ability to couple with hydraulic models to translate into instream concentrations.