Main Roads WA (MRWA) Anstey Artificial Wetlands
During construction of the Forrest Highway from Perth to Bunbury, wetlands and damplands south of Stake Hill Rd, Baldivis were in-filled to make way for the highway. As an offset for this loss, MRWA created additional damp and wetland areas, to capture drainage and ensure water quality was maintained prior to entering the Serpentine River. Referred to as the Anstey Wetlands, they consist of a complex of shallow, seasonally-inundated wetlands that have been shaped and vegetated to simulate seasonal wetlands of the Swan Coastal Plain (SCP).
MRWA commissioned WRM to assess the success of the wetlands, in terms of providing ecologically healthy, functioning ecosystems. As part of this process, WRM undertook a comprehensive aquatic sampling program of the Anstey wetlands, and then assessed the ‘ecological health’ of the wetlands through comparison with the range of ‘performance indicators’ that were developed as part of the work at Beenup.
WRM found that the constructed Anstey wetlands appeared healthy, and provided a level of ecological function that is comparable to the lower range of natural wetlands of south-west Western Australia. As these wetlands mature, it is expected the performance against these indicators will improve.