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Contrary to what you hear and read in the media, the Channel Deepening Project is NOT a fait accompli.

Very serious outcomes from the August 2005 Trial Dredge Program (TDP) were only released to the SEES Inquiry last week – on the second last day of the hearings. So serious are they that the Inquiry Chair saw fit to call for further public submissions on this new evidence.

The time frame is severely limited – now only 7 days. But it is critical that in that time each and every one of us respond. Your reply does matter. PLEASE ACT NOW.

The deadline is 10am Monday 13 August.

Here are the recent facts. New submissions are meant to be to this new information only, so a lengthy reading of earlier material is not required:

1. The Trial Dredge Program of August 2005 was not a success as claimed. Damage done at the Entrance is much greater than admitted at the time.

• The volume of rock which fell after trial dredging was greater than claimed
• The rocks fell to greater depths than claimed
• They were not “gathered” by the dredge
• Rock at the Entrance is continuing to disintegrate and mobilize, causing further scouring of the channel.

2. That was not the “end of the matter”.

• There has been delamination and mobilization of rock layers - slabs up to 3m² and 400mm thick can be lifted by current and swell (This was NOT expected and is raising issues of long-term stability)
• PoMC claims that a hard layer of rock at 22m depth will limit further scour, but scouring to 25m depth has occurred in some places
• On 30 July PoMC declared scouring might continue for 30 years (coincidentally the length of the project), but it is not clear that there is any time limit to scouring as no evidence is provided.

3. What we know (or have been told) up to the present.

• Modelling of the Entrance ship channel is now being done on the basis of 22m depth to take account of scour (compared with the original max depth of -19m). 
• Extensive further research and analysis is needed to determine the effects of dredging into this rock which is prone to cracking and erosion beyond modelled “predictions”
• The combined effects of further rock scour, and rock delamination, have not been adequately assessed.
• How much of the rock disintegration is due to dredging and how much is due to the natural susceptibility of the rock has not been described.
• The further influence of tidal currents at 22m and below is not known.
• The effects at shallower levels of extreme storm events are unknown
• The ability of the PoMC to periodically “clear up” extra rock which will result is also unknown, despite new arrangements (Tuesday 31 July)
• All impacting factors have not been put in to the model which is meant to show what the likely outcomes will be (Raisbeck SKM Report). The model only looked at the effect of slope and gravity on mobile rock