Rainwater, storm water and recycled water are becoming increasingly important to provide better water services for Victoria.
Most recycled urban storm water is used for non-potable uses, such as watering gardens. It is understood that stormwater can carry a range of commonly used pesticides and herbicides, which could impact the water quality and needs to be managed if a risk exists.
The Victorian Centre for Aquatic Pollution Identification and Management (CAPIM) recently conducted surveys of some streams and wetlands within suburban Melbourne and found that some herbicides are commonly present in urban storm water at concentrations that may impact aquatic ecosystem health. This study is one of the rare occasions that herbicides have been measured in Australian storm water at environmentally meaningful concentrations. The presence of these herbicides raises concerns about whether these chemicals are being removed during storm water treatment. It also raises concerns about what type of monitoring should routinely occur in recycled storm water programs.
Herbicides regularly observed in Melbourne are atrazine, dicamba, MCPA, and simazine. As multiple substances may be present in storm water, it is difficult to determine the combined effect of chemicals. Therefore, the broad aim of this project is to use a range of novel sample collection and preparation techniques prior to new multi-residue analytical and integrative bioanalytical techniques to assess storm water quality across Melbourne. Specifically, this project will:
- understand if the cumulative affect of these known herbicides and pesticides present a risk;
- use a broad spectrum of sites to help distinguish the influence of land uses in the urban environments on micropollutants (primarily herbicides), by chemical and bioanalytical analysis of collected storm water samples;
- assess what types of water quality treatment devices used in water sensitive urban designs are capable of removingthese micropollutants (by literature review and field observation); and
- develop guidelines for efficiently monitoring of micropollutants in urban storm water treatment devices (by literature review and field observation).
This research project will provide valuable information on the quality of urban storm water within Victoria and make recommendations on appropriate treatment required to ensure that this water is suitable for use on open space areas.