Degree Name

Bachelor of Environmental Science (Honours)




School of Earth & Environmental Sciences


Waterways represent an important part of the urban landscape due to the potential human and ecological health impacts associated with them. As a result of this, considerable effort is invested in the improvement and protection of urban stream water quality. This study examined the treatment efficiency of six stormwater quality improvement devices (SQIDs) located across the Sutherland Shire. A range of water quality indicators were assessed and the concentrations of these constituents were measured at both the inflow and the outflow, to determine the relative differences between these two points. These data were compared with established guidelines for stormwater quality, namely the Australian Runoff Quality Guidelines by Wong (2006), to provide an indication of pollution in the catchment and the operational efficiency of the SQIDs. Rainfall data and land use zoning maps were used to identify potential sources of pollution in the catchment and explain the pattern of constituent concentrations detected. It was found that four of the six sites examined were functioning relatively well and were achieving adequate reductions in the pollutant loads arising at the inflow. While the results of this study did not clearly demonstrate which treatment device design was superior, it showed that it is necessary to specifically construct installations for stormwater treatment, if they are to be successful. Modifying existing infrastructure, originally designed for other purposes, is inadequate, as illustrated by the two poorly functioning systems identified in this report. By investigating urban water quality and SQID operation, decision makers can become better informed, thereby improving stormwater and urban catchment management in the future.