Conference Agenda

Stormwater is a known source of faecal contamination of receiving waters in urbanised areas. WSUD systems are proposed as a promising way of decreasing pollution levels within the stormwater discharge. However, application of these systems at the real estuarine scale can be costly and the effects on the receiving waters remain at best a guess. Therefore, modelling of both receiving water faecal pollution dynamics as well as the faecal pollution in the raw stormwater runoff and the selected WSUD treatment technologies for these stormwater inputs can reveal the magnitude of these effects within the receiving water environments, helping guide future mitigation strategies and investments towards the optimal solutions for improvement of microbial water quality. In this study, a combination of 3D process-based and conceptual models was applied for simulation faecal microbial dynamics in an urban estuary, stormwater inputs and biofiltration of the stormwater to assess the effect of WSUD treatment on over 200 stormwater drains discharging directly into an estuary. WSUD treatment of stormwater inputs showed potential but limited effects on the overall microbial water quality, which was related to the magnitude of stormwater inputs in comparisons with other faecal contamination inputs in the estuary.