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Q. How much area at The Heads was dredged during the Trial?
A. 150 metres in length and approximately 29,000 cubic metres of rock was removed. 6,000 cubic metres (around 9,000 tonnes) fell uncontrolled down the face of Lonsdale Wall destroying ancient sponge gardens and corals.

Q. What is the total amount planned for removal at The Heads if the project was to proceed?
A. 1.1 kilometres along the lip of Lonsdale Wall and The Plateau, with a total volume of approximately 500,000 cubic metres of rock. That's about 990,000 tonnes of rock, kelp and sponge gardens, brightly coloured corals - habitat for hundreds of species- and what was once beautiful underwater scenery. This is approximately 10 times the length of the trial, and over 20 times the volume.

Q. How did the rockfall during the trial occur? 
A. At several points along the Wall, the lip was breached by rock which was not sucked into the Trailing Suction Hopper Dredge as designed to do. This rock, of various sizes, tumbled down the wall into the canyon, damaging the sponges and corals on the wall as it fell. Some rock is now resting at the bottom of the 100 metre canyon. Some is still at various depths on the wall, and is moving around with the swell and current, potentially doing further damage to the sponges and corals.

Q. Why does PoMC claim the trial dredging ‘successful’ when the rockfalls at The Heads was clear evidence that the technology failed to meet the environmental standards required?
A. Blue Wedges cannot explain why the PoMC makes this claim. PoMC has demonstrated that it can move rock, but not without significant damage and consequences. It admits in its SEES that more rock will fall if the project proceeds. It also admits that the trial dredge caused 6,000 cubic metres of rock to fall down the canyon wall - not the 20 or so cubic metres they announced at the time.

Q. Often, different or even feral species quickly establish in damaged areas. What might happen if sponges and corals damaged by rockfalls do not recolonise with the same species structure as prior to the trial?
A. It is possible that we could lose one of Victoria’s best dive sites and an irreplaceable area of habitat for many unusual and some unique species.


Q. Is the proposed design of the channel at the heads adequate for the safe passage of larger oil tankers?
A. PoMC claim that it is, but this is contrary to the result of sea pilot simulator tests run after the EES and reported in The Age of 18th December 2004, where approximately one third of test runs grounded. Our expert advice is that risks of grounding will increase.

Q. Why does PoMC still allow single skinned (one single sheet of steel for the hull) oil tankers into the Bay?
A. We cannot understand why, as any grounding would be more likely to result in an oil spill or loss of other contents. We have not heard a response from PoMC on this issue.

Q. Has an economic analysis been done?

A. Yes- but only an analysis of what the Port contributes to the economy - not what the Bay contributes to the economy in tourism, recreational and commercial fisheries and aquaculture, property values, cleaning up almost 50% of our daily sewerage via Werribee treatment plant, general amenity and open space, and swimming and  sailing in beautiful clean water - all for free! We believe an analysis of those services would show the Bay contributes much more to the economy than does the Port.


Q. What testing of Yarra toxics has been done?
A. Considerable testing was done in preparation for the first EES. Much of this evidence was discredited by independent witnesses, and by the Panel itself. Further testing has been undertaken since then according to the PoMC, and is contained in the S-EES. It is alarming.

Q. What turbidity modelling has been done for the Yarra dredging?
A. None was done for the first EES - and we were told by PoMC that their science was state of the art! It was stated that the assumption was that it would be uniformly turbid from bank to bank. This is in spite of the Yarra being tidal. Turbidity modelling in the Yarra now indicates a toxic plume would spread from bank to bank from Bolte, past Docklands and out into the North of the Bay and its coast, such as Williamstown and Port Melbourne.

Q. If toxic sediments from the Yarra are disposed into the bay, how can they be permanently contained and prevented from polluting the food chain?
A. The PoMC plans to construct an underwater "bund" out of clay from the Williamstown channel dredging, then dump the Yarra sediments into that, then sift a 50 cm layer of sands from the South of the Bay over the top of the sloppy Yarra sediments. This process would take about 140 days to complete, and may remain uncapped for up to 5 years. The evidence that the cap would safely encase the toxic sediments in perpetuity is not compelling.  


Q. Is the PoMC aware that other options to channel deepening, such as national rail links, are a realistic proposition?
A. PoMC claims that no other option is feasible, and it is committed to the present project. As a Corporation, PoMC is interested in its plan for the future, not exploring what might be other realistic or better alternatives for the future of Melbourne and the Bay. We suggest this is a Federal issue, and the Federal government should look at using a mix of transport modes to suit the environmental and social needs of each region. PPBay for example has reached its ecological limit. Here we could employ current sized ships that fit into the Bay, any excess containers could be off-loaded at existing deep water ports already in Australia. Those excess containers could complete the journey to Melbourne by rail - and arrive quicker than if left on the ship!  The lightened ship could then complete its journey to Melbourne.

Q. Why aren’t other alternatives being properly studied?
A. In part because the Terms of Reference/Assessment Guidelines do not include looking at alternatives. We can only speculate why these Guidelines were written so as to exclude looking at other alternatives. It might also be because government has decided to pursue the option put to them by the promoters of the project (PoMC) without considering other, potentially much more sustainable options.

Q. Is the PoMC aware of the interest being shown by various businesses eg: Coles Myer, the National Party, Tamworth Council and others in a Brisbane-Melbourne rail link?
A. PoMC remains committed to the present project. We think the state government should be reminded that there are other alternatives. Federal government has announced it support for the Melbourne-Brisbane in-land rail link. We believe that the Federal government should be lobbied to encourage the fast tracking of the rail link, so that deep draught vessels cold unload enough cargo in Brisbane to achieve 12.1 metres draught limit for Melbourne, then continue their journey to Melbourne.  







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