The recently released Western Port Local Coastal Hazard Assessment reports illustrates just how much of Western Port is at risk of inundation or erosion (and in some cases both), by climate change induced storm surges and sea level rises.
In August this year the Bass Coast Shire Council endorsed a planning scheme amendment on Land Subject to Inundation Overlays (C82) based on these findings.
More recently the Port of Melbourne select committee inquiry into the proposed lease of the Port of Melbourne heard from the Preserve Western Port Action Group.
At the hearing on 28 October 2015 the Chairman of the Preserve Western Port Action Group Jeff Nottle advised the Inquiry:
“...a business case and or cost-benefit analysis for a container port at Hastings needs to include all the costs that impact on the region.”
In addition Mr. Nottle added: “...cost estimates for Western Port.... need to include the impact of increased erosion and sediment flows arising from the dredging in a very high tidal flow environment. Current erosion issues will be accelerated and exacerbated with severe impacts, particularly in the north of the bay and on the north shore of Phillip Island, which includes Cowes and Silverleaves.”
“....the analysis that we have used has been based on the Victoria University supply chain institute........... 18 million cubic metres worth of dredging at the wharf side and 6 million cubic metres in the approach channel….”
Following the Inquiry one of Australia’s leading geomorphologists Associate Professor David Kennedy of the University of Melbourne considered the Victoria University findings and the Western Port Local Coastal Hazard Assessment reports. Professor Kennedy has since stated:
“I can conclude that the proposed development is almost certain to have major environmental impacts on the marine and coastal environment of Western Port Bay.”
“There will be immediate effects from dredging particularly associated with suspended sediment and its impact on the benthic intertidal and sub-tidal communities. A larger concern are the changes in hydrodynamics and associated sediment movement that will be associated with the development.”
“There is a very high risk of greatly increased erosion throughout the northern, western and southern shores of Western Port including the eastern shoreline of Bass Coast around Coronet Bay and the Phillip Island north shore. A general lack of knowledge of sediment transport pathways within the Bay mean the potential impacts could be more widespread than inferred here as there is likely be strong connectively between sedimentary systems around the entire bay.”
In responding to this new report Jeff Nottle added:
“This independent specialist analysis brings into focus the potential damage to Western Port properties and coastal foreshores and beaches that will arise from the dredging associated with the construction of a container port at Hastings. The erosion and inundation caused will not be gradual and imperceptible, it will be obvious as the Western Port Local Coastal Hazard Assessment reports give us a baseline for erosion and inundation without the dredging for the port.
We believe all proponents for the construction of a container port at Hastings should support the establishment of a Western Port Erosion and Compensation Fund as part of a business case for Hastings.The fund could then be accessed by affected property holders and coastal land managers to restore the coast or to provide compensation.”