Our Indirect Environmental Impacts

Our Eco-footprint

Our Eco-footprint measures the impacts of human activity on earth and estimates the area of land needed to support a household, a school, a business or a society.

City West Water’s Eco-footprint was last calculated in 2003 for the 2001–02 year and is due to be calculated again in 2006–07.

The Environmental Impacts On Water Catchments (Upstream Impacts)

The drinking water catchments to the north-east of Melbourne cover large areas of land. The capture of water for drinking use can reduce the amount of water that is available for rivers and this can impact on river health. Land management practices can also affect the environmental health of catchments, the amount of water harvested and the quality of water.

To address these potential impacts, we participated in the development of the Central Region Sustainable Water Strategy which can be viewed in more detail here.

Ongoing water conservation in Melbourne can prevent the need to construct more dams to supply the city and can help avoid the environmental impacts of dam construction and operation.

The Environmental Impacts Of Managing Sewage (Downstream Impacts)

We transfer approximately 93% of the sewage and trade waste we collect to Melbourne Water’s Western Treatment Plant, with the remaining 7% treated at our Altona Treatment Plant. It is treated and then discharged into Port Philip Bay from both plants, in accordance with the EPA Victoria licence standards. The environmental consequences of treatment include the generation of greenhouse gas emissions, the creation of biosolids that may contain contaminants like heavy metals, disturbance of land and the discharge of residual nutrients and other substances left over from the treatment processes into waters.

The Altona Treatment Plant treats sewage from nearby suburbs which contains relatively high levels of salt due to infiltration of salty groundwater into the sewers.

City West Water monitors the impact of the treated wastewater discharged into Port Phillip Bay and reports the results to the EPA Victoria. Such studies are completed regularly and have shown that the Altona Treatment Plant has a negligible impact on Port Philip Bay.