When a Wastewater Treatment Plant (WWTP) is to be decommissioned, environmental harm on-site or off-site must be avoided before, during and after the decommissioning phase. Land uses that are allowed under the relevant zoning of the land must not be prejudiced by residual pollutants on the land.
For WWTPs that treat more than 100 kL per day of wastewater ("Level 2" WWTPs as defined in the Environmental Management and Pollution Control Act 1994 (EMPCA)), Permits or Environment Protection Notices usually require a Decommissioning and Rehabilitation
Plan (DRP) to be submitted to the Director of the Environment Protection Authority prior to decommissioning. The guidelines given in Decommissioning of Wastewater Treatment Plants, Nov 2010 provide information to help prepare a DRP.
Decommissioning of Wastewater Treatment Plants Nov 2010 (54Kb)
For non-Level 2 WWTPs, the relevant local council should be consulted about decommissioning requirements under the local planning scheme. The guidelines may be useful as a reference in this case.
Wastewater treatment storages classified as ‘dams’ under the Water Management Act 1999 may require a permit from the Assessment Committee for Dam Construction
prior to decommissioning, or for alterations to the storage. Further information can be obtained from the Water Management Branch.