Evaluating the water quality of stormwater runoffs in urban area

Abstract

This paper presents the results of stormwater quality monitoring from four constructed wetlands located in residential and industrial catchments. Preliminary results revealed that pollutants’ types and concentrations vary depending on the catchments’ characteristics. It is found that the residential catchments often hold higher total phosphorus and suspended solids, while the industrial areas are found with high concentrations of Iron and Strontium. Nonetheless, high metal concentrations are observed in both catchments, raising concerns about the effectiveness of stormwater treatment devices and the current guidelines adopted in the design and construction of these systems. While it is found that all catchments displayed exceptional levels of pollutants that are not safe for the freshwater environment, the pollutant concentrations remained below the average concentrations in the Melbourne area. Less commonly discussed metals such as Barium and Strontium were found in all water samples with concentrations greater than the values discussed in the literature. During the investigation, challenges were faced due to the voluntary nature of the guidelines and the lack of data on trace metals. It is, therefore, recommended that further monitoring is required to confirm the changes in stormwater runoff quality and to assess the appropriateness of the current guidelines for improved management.