ocean current

Geomorphic Impact of the Proposed Port of #Hastings #phillipisland

Last year we approched A/Professor David Kennedy from the University of Melbourne for information on what the likely Geomophic impacts the Port of Hasting Development would cause - this was his response;

Thank you for the information provided by the Western Port Local Coastal Hazard Assessment and the Preserve Western Port Action Group Discussion Paper regarding the proposed development in Western Port, especially the plans for a single channel deep-water channel and associated mooring and swing basin at the northern and southern ends of the this channel.
Based on my > 15 year experience in coastal geomorphology including recent work in Western Port and similar structurally controlled estuaries in New Zealand

...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 subtidal communities. A larger concern are the changes in hydrodynamics and associated sediment movement that will be associated with the development.

A deep-water channel will lead to the propagation of open ocean waves further into the estuary as well as enhance the size of locally-generated wind waves. As the coastline of Western Port has evolved under low energy, fetch-limited, conditions any increase in wave energy will result in significant shoreline erosion. All shorelines adjacent to the area of dredging will be affected. The increased channel size will also likely increase the tidal prism within the estuary.

The potential for major landscape change is not restricted to just the channel area. The eroding shoreline of the north eastern side of the Bay will also be affected.

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.

Best regards,
A/Prof David Kennedy
Coastal Geomorphologist
Assocaite Professor
School of Geography
The University of Melbourne
Parkville, Vic, 3010