Contaminants are substances that are either present in an environment where they do not belong or are present at levels that have the potential to harm human or environmental health. Contaminants can be natural in origin such as some metals or man-made such as organochlorine pesticides.
Some examples of contaminants that may be found in our waterways include:
- metals
- pesticides
- petroleum by-products
- anti-fouling paints
- bacteria and
- nutrients
Contaminants are widespread in our waterways in one form or other, although certain areas typically contain higher concentrations and more types of contaminants than others. These areas are often in the vicinity of industry, urbanisation and agriculture. The Department of Water assesses the concentrations and types of contaminants in a variety of water bodies including river and estuary systems, stormwater drains and groundwater. We do this through a range of water quality, sediment quality and ecotoxicological techniques.
Understanding the types and concentrations of contaminants both within and entering our rivers and estuaries will assist the Department in assessing river and estuarine healthand may also be linked to fish kills.
Waterways currently being assessed for contaminants include the Swan Canning and Peel Harvey estuaries, the Leschenault, Vasse Wonnerup, Hardy, Broke, Walpole Nornalup and Wilson Inlets, the Princes Royal and Oyster Harbours and the rivers, creeks and stormwater drains feeding into these systems.
A range of contaminants are also assessed by the Department of Environment and Conservation in relation to environmental exposure and contaminants such as metals and bacteria are assessed by the Department of Health in relation to human exposure.