Here is a selection of submissions which the authors have agreed we may display for everyone to read. If you wish to reply and comment on anything here, please use the Letters to Blue Wedges facility (under the Documents tab on this site).


Channel Deepening Project: Submission


The Dangers involved in Channel Deepening where Global Warming induced Rising Sea Levels are an established fact.


Port Phillip Heads provides an important restriction on tidal movement between the Southern Ocean and Port Phillip Bay. The result is a ‘modulation’ of tidal rise and fall, so that the upper and lower limits outside the heads are different to the limits inside the bay, which gives us a lower maximum and higher minimum bay sea level. This phenomenon is due to the fact that the water volume of ‘the bay’ is such that there is not enough time during the period of ebb and/or influx of the tide for enough water to pass through the restrictive channel of ‘the heads’ to allow equal sea levels to become established on both sides. Conversely, Westernport Bay is smaller with large openings to the Southern Ocean, and has larger tidal variations.


Any deepening of the channel through the heads must necessarily reduce the restriction and thus increase the tidal flow, and this inevitable outcome should be measured in light of our new-found acceptance of the fact that sea levels are remorselessly rising due to global warming. Rising sea levels are undeniably a future threat to coastal cities such as Melbourne.


The EES for the Channel Deepening Project makes the following claims for tidal variations following the projected modifications to the heads:


Change in average low tide       - 15 mm

Change in average high tide       + 8 mm

Change in tidal currents (presumably velocity) <2%


It is stated in the EES data, that 550,000 cubic metres of rock will be removed in the process of deepening the reefs of Pt Nepean Plateau (9.5 Ha) from 14m to 17.3m, plus the Rip Bank reef (‘patches’ area not specified) taken to the same depth. From the EES plans, the latter works appear to represent a further area of approx 10-15 Ha.


In the absence of specific geometric detailed information, I have made some fluid flow calculations based on a conservative estimate of the cross-sectional area of rock being removed from an area of near maximum tidal current flow rate, averaged over a tidal cycle. I arrived at a figure of 0.0065% volume change in the bay as a result of the changes in geometry at the heads. This equates to a potential +6 cm change in flood tide peak, which is in contrast to the EES claim of +8 mm. Although my figures are based on a mixture of values taken from the EES and Appendices, and on some necessary careful estimates, I believe there is serious reason for caution in this issue, and the EES figures should be independently reviewed.


 I believe a rise in general sea level will definitely change the water levels inside the heads as well as outside. The mysteriously rapid and threatening rise experienced by some low-lying South Pacific atolls such as Mortlock and Cartaret Islands gives us warning that the consequences of actual sea level rise can exceed the expert’s predictions.


With comparatively small changes of about a centimetre /decade this problem would not greatly threaten us in the short term, but long term uncertainties are a different issue, particularly if we are augmenting the problem by deepening the channel. However, if predictions of huge glacial discharges from Greenland and the West-Antarctic continent, resulting in changes measured in metres, were to happen in the foreseeable future, Melburnians would be wishing the heads had been left alone by the Bracks Government (and desperate efforts may be undertaken to re-instate tidal levies).


Further to the above considerations, the destruction of reef ecosystems at the heads over an area exceeding 20 Ha, plus the rock fall and rubble consequences in the chasm, are clearly undesirable and difficult to justify for a perceived short-term economic benefit. Surely it is logical to provide for the largest ships at Westernport, if their service is considered essential, leaving the majority of current sized vessels with good access to Port Phillip Bay. Future shipping transport developments will see larger capacity container ships with shallower draft than current vessels entering service, which will obviate the need for radical changes to the bay channels.


According to Dr Phillip Bock, Research Fellow of  Deakin University and world authority on Bryozoan species, the Port Phillip Heads, chasm and surroundings is an internationally famous biodiversity ‘hot-spot’ for these and other marine organisms, and deliberate damage to this area would be a tragedy and embarrassment for Australia and the world’s marine science community.


I trust the above matters will be seriously considered before a final decision is reached on changes to the bay that can still be avoided, but will have far reaching consequences if enacted.


Bernard Mace

Scientist, Marine Engineer


7 May 2007


Submission: Channel Deepening SEES DSE Planning Panel 8 Nicholson St Melbourne


Questions for the SEES Panel that could not be answered from the Supplementary EES.




(A) What is the total cost of the Channel Deepening Project a) best case b) worst case?


What is the annual cost of maintenance after completion of the project over and above channel maintenance over and above existing annual (or annualised) maintenance costs.


What is the likely levy on shipping per standard container/per tonne of weight/other

a) best b) worst case?


(B) What is the value of the potential liability of the Port of Melbourne Authority, contractors and or State Government with and without the Port Facilitation Bill minimum and maximum exposure to claims for compensation following further opening of heads of increased tidal flow and change of currents from:

1)      Waterfront/estuary side property

2)      Beach front infra structure/property public and privately owned

3)      Sewerage/industrial waste water - and from prolonged  turbidity and the loss of seagrass beds from 2 years (PoMC consultants) to 10 years (commercial fishermen based on Geelong arm dredging affect experience) on:

4)      The loss of fish production in a) Recreational Fisheries b) Commercial Fisheries c) Aquaculture

5) Tourism including on beach recreation, yachting and general charter boat operations and diving charter


(C) What is the value of the potential exposure for liability to financial claims through litigation of the Port of Melbourne Authority, its contractors, members of the SEES Panel and/or State Government with and without the Port Facilitation Bill due to the impact of dredging Yarra River is if it generates smells and/or toxins that necessitate evacuation or blue green algal blooms 

1)      From the CBD and businesses along the Lower Yarra

2) the losses to businesses from the cancellation of public events normally staged on the Yarra River e.g. Moomba. - and due to spoilage of toxic spoil during excavation, transport to spoil grounds, at spoil grounds and in the event of the compromise of spoil holding structure of a wide range of toxins that can accumulate in edible marine life from:  

i/ The recreational fishing sector and supporting industries

ii/ The commercial fishing sector and supporting industries

iii/ Tourism operators along the bay including charter fishing and River

iv/ Victorian Tourism operators generally if the bay should become widely known the Port Phillip Bay or its eastern beaches had become contaminated by toxic spoil.


(D) What monitoring will there be of:

a)      stocks of commercial and recreational fish species before and after the projects completion, for how long after completion, and who will undertake the monitoring and how will the data be made available to the public?

b)      b) toxin levels in commercial and recreational fish and molluscan species before, during and after the completion of the project, by whom and how will the results of this testing be made available to the public


(E) What will be the net financial benefit of the project to Victorian consumers as measured by standard/average consumption /expenditure patterns?


Bob McDonald







Submission on the SupplementaryEnvironment Effects Statement for the proposed Channel Deepening project in Port Phillip Bay

Prepared by Jenny Barnett May 2007




The VNPA strongly opposes this project because the Bay’s assets are too precious and the risks too high.  The very many risks are cumulative so the chances of something going seriously wrong are great.  The multiple possible impacts on a large number of areas and environments, and the unpredictable interactions in the system, make for many uncertainties and a strong possibility that unforeseen (or even foreseen) disasters will occur.  The risk is not worth it to allow a relative minority of larger ships into the Bay with limited economical benefits to the general public.  Alternatives such as use of other ports for larger ships, encouragement of use of the Melbourne Port by medium sized ships and improvement of the National rail network are far preferable to taking this risk.





The provision of only 6 weeks to digest and analyse 15,000 pages of documents containing complex technical information suggests that the government does not seriously wish to have the project scrutinised.  With the level of resources available to us, and the multiple demands on our staff and volunteers, we have been unable to examine the documents to anywhere near the extent that that we feel is necessary to respond to such a significant proposal.  If there are errors or omissions in our submission because we have missed some aspect in the documents we make no apologies because of the sheer size of the material. Instead we reserve the right to add to our submission at the panel hearing on any relevant matter.


The proposal to have the Panel Hearing very shortly after the submission deadline further exacerbates this situation.  Even more alarming is the proposal to limit the questioning of witnesses and to limit the length of the panel hearings to only 4-7 weeks. As the Panel is itself only given a few weeks to produce a report then this will make the situation even worse.  All this makes it impossible to examine this complex proposal to the depth required. In addition, unfortunately none of the Panel members have had the benefit of sitting through the details of the previous EES, making their task even more difficult. 


Compounding the situation are the limitations placed on the panel preventing them from considering any alternatives to the proposal (such as other ports or transport options) or the cumulative effect of the maintenance dredging that will follow indefinitely.


Proper analysis by the public, independent experts, and the Panel cannot be done quickly.  The long-term impact of all aspects of the proposal and whether there are other means to achieve the same end are vital considerations.  Our Bay is a vital asset to our State and deserves better.





The Bay is too precious

As outlined in the EES and the SEES, the Bay has a vast array of important values including high biological diversity, complex ecosystems, Marine National Parks and Sanctuaries, internationally listed wetlands and sites of archeological and geomorphological significance. A large number of species in the bay are endemic to the region and most of the Bay’s species are found in the southern half of the bay where extensive dredging and dumping of the material is to take place.  There are threatened species such as sea-horses, snapping shrimp, ghost shrimp, giant seaweeds and unique ‘sponge gardens’ in the Rip. Thirty-three species are known to be ‘of conservation concern’ with much still unknown about the vast majority of species in the Bay. There are seals, dolphins, penguins and occasionally whales.  There are also important uses including a wide range of recreational and tourism activities, fishing industries, aquaculture and other marine-based industries.


The Bay also acts to help de-nitrify the runoff and treated sewage that is discharged into the Bay in large quantities. The sensitive benthic ecosystem is critical in this respect and irreversible damage of its ecosystems has been suggested as a possible outcome.   It is also possible that seagrass losses will be irreversible with long-term impacts on fisheries and the overall ecology of the Bay.   No matter how remote this possibility, it is a chance we should not be taking


The Bay is also of great economic importance for a wide range of reasons including ecological services (such as de-nitrification), fish resources, tourism, recreational and so-on.  The economic value of these, if put at risk, would far exceed claimed economic benefits of the proposal, and are also enjoyed far a far wider range of the general public.



Many impacts are certain or likely


The proposed dredging program is massive on a world scale and long in duration.  As outlined during the 2004 EES hearings it is four times the size of the next largest dredging operation anywhere.  It will affect large areas in the north and south of the Bay.  Port Phillip is the largest enclosed bay in the world, with complex and unique marine ecology.  It is no wonder that assessment of the proposal is complex and the project controversial.


The sheer volume of material to be removed (about 25 million m3 initially and 17 million m3 for maintenance in the next 30 years), and the multiple and difficult to control problems associated with moving it, mean some impact is inevitable.  The SEES admits this but claims such impacts will be ‘short-term’ or ‘limited’ with most impacts lasting only 1-2 years. Where, after 100 years of dredging in the Bay (at a much lesser scale), are the comprehensive studies of the impacts of past dredging that provide the basis for these risk assessments?  The physical change to the Bay will also mean some permanent changes in the Bay’s physical environment which again are described as ‘limited’.


Impacts which particularly concern the VNPA include:

  • Impacts on shorter-lived fish, especially those living near or passing through the mouth of the Yarra and/or with migration patterns in and out of the bay

  • Impacts on penguins at St Kilda

  • Impacts in the wider bay on penguins, seabirds, dolphins and seals due to turbidity affecting their feeding because of poor visibility and/or reduction in prey numbers.Risk of toxic algal blooms in the north of the Bay

  • Permanent loss of sea-grass in the south east of the Bay

  • Rockfalls in the Entrance resulting in loss of slow growing biota and damage in the Marine National Park

  • Turbidity and sedimentation and their myriad and wide reaching effects

  • Disturbance and mobilisation of contaminated material in the north of the Bay.

  • Accumulation of contaminants in top-order carnivores such as larger fish, seals and penguins

  • Mobilisation of nutrients and algal cysts - including the possibility of upsetting denitrification processes when combined with turbidity and sedimentation

  • Changed currents, - effects on transport of larval fish

  • Underwater noise and vibration and its effects on migrating fish and penguins

  • Changed tidal ranges, currents and wave patterns - potential impacts on salt marshes and areas such as Mud Island

  • Risk of larger oil spills- with potential wide ranging impacts.

These impacts are outlined below.  To match the layout of the SEES, issues are largely dealt with area by area except where some issues overlap.


Some of these impacts and risks on their own may seem ‘minor’ or ‘medium’ (but see comment on risk analysis below). However, taken in total, and especially if all does not go as predicted, there is a cumulative risk of some serious losses in the medium or long-term, especially if the system is periodically re-disturbed with not-so-small maintenance dredging.


In addition, some possible scenarios such as oil spills and widespread denitrification and algal blooms could result in catastrophic outcomes.  While these may be unlikely, they nonetheless represent a real gamble.



Bias In The Risk Analysis


The risk analysis employed, and the SEES in general, play down the risk to the environment. Different standards and criteria are applied to economic considerations than to the environment and social considerations.  If the shipping industry suffers more than one month’s stoppage this is rated as an ‘extreme’ consequence (p5-54) and as ‘moderate’ when it is for only one week. 


In contrast, for the various aspects of the environment and tourism permanent loss is required to get an extreme rating and effects that last for years are only rated as ‘moderate’.  Over 10 fatalities or major health impacts on over 1000 individuals are required to be assessed as ‘extreme’ while 1 fatality and/or 100 persons suffering major illnesses or injuries is considered ‘moderate’.





Ninety percent of the river bed in the Yarra for 6 km from the mouth, up to (and including) Appleton Dock, will be removed (3.37 million m3) together with 5% of the seabed in Hobsons Bay (2 million m3).  Impacts will include gross removal of habitat, increased turbidity, re-suspension of contaminants, noise and vibration and possible stimulation of algal blooms.


Recovery of various invertebrate and microscopic biota in the river and seabed will take up to one year, if the SEES is correct in its predictions.  Fish and other fauna dependant on these such as Black Bream will be affected for at least this period.



Seahorses and pipefish


The SEES notes that a number of EPBC protected seahorses, seadragons and pipefish (syngnathids) are found in seagrass and reef algal habitat in Hobsons Bay and some are in the Yarra River estuary (p12-30 – 12-35).  Twenty-four species are found on the wider Bay, however, the SEES main report is vague about numbers of species in each area.  Impacts from turbidity and high noise percussion are dismissed as ‘minor’ on the grounds that the various species are found elsewhere in the Bay or Australia.  Australia has about a third of the world’s syngnathid species with this group being sparse or absent in many other parts of the world.  Protection of our exceptionally diverse fauna is important even if individual species are found elsewhere.



Fish in the Yarra


Estuaries are usually more diverse than rivers. In addition to the above syngnathids, the lower Yarra has records of 32 native species between East Melbourne and the mouth (see table below) including at least 10 species of freshwater fish from further up the Yarra that are diandromous, (species that pass between freshwater to marine/estuarine systems and back, in either direction, as part of their lifecycle).  They include 4 species of gallaxids, one of which is the Mudfish.  There are also five mainly freshwater species that frequent lower stretches, 3 species that frequent both freshwater and estuaries, 8 species confined largely to estuaries, and 6 largely marine species.  These were detailed in one of our earlier submission to the 2004 EES.  But, in spite of our provision of this information, the SEES ignores the overall fish diversity and only considers those fish that are listed as threatened, or are of commercial value.


In spite of this diversity, there has never been a fish survey between Melbourne and the sea save for one day with gill nets (at Spencer St Bridge, Victoria dock, Westgate Bridge, Newport power station) plus one dip net near Newport power station.  In contrast Dights Falls in Kew has been intensely surveyed.  Most lower Yarra fish records are either opportunistic or are very old, dating back to the 19th century.  For those fish with only old records, it should not be concluded they are no longer there, especially smaller non-commercial/recreational fishing species.  For instance, the single dip net survey at Newport in 1989 revealed the only record for the Bridled Goby and only the second record for the Blue-Spot Goby (previously recorded in 1935).


We are disappointed that the SEES has still not conducted base-line surveys for the smaller fish such as the gobies, gudgeons, hardyheads and smelt in the lower Yarra, although at least the invertebrates have now undergone some limited sampling.


Native Fish in the lower Yarra*



#Grayling, Tupong, Spotted Gallaxid, Broad-finned Gallaxid, Common Gallaxid, #Mud fish, Short-finned Eel, Short-headed Lamprey, Pouched Lamprey, Australian Bass.



#Macquarie Perch, #Trout Cod, #Murray Cod, Golden Perch, River Blackfish.



#Yarra Pigmy Perch, Australian Smelt, Flat-headed Gudgeon.



Blue spot goby, Bridled goby, Tamar River Goby, Small-mouthed Hardyhead, Black Bream, Estuary Perch, Yellow-eyed Mullet, Mulloway.



Sea Mullet, Sand Flathead, Australian Salmon, Green-back Flounder, White Trevally, Southern Anchovy.



* This does not include syngnathids which are additional. About another 7 strictly freshwater native fish species are further up the Yarra and are unlikely to be affected and there are also at least 8 exotic species (some of which occur near the mouth).
# = species listed under EPBC and/or F&F Guaran

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