Posted on May 9, 2016
By Joel Maxwell, stuff.co.nz
Dredge it or lose it, is the message from CentrePort as public consultation launches on plans to scoop a 7-kilometre channel for heavy sea traffic into Wellington Harbour.
CentrePort is about to apply for resource consent to dredge 6 million cubic metres of sediment from the harbour floor – enough to fill a million concrete trucks – which would be dumped into the sea off Fitzroy Bay, just outside the harbour’s entrance.
A 7km channel will be cut from the mouth, reaching 17.2 metres at its deepest point, at a cost of between $37 million and $44 million.
The work would impact an aquifer that supplies water to the region, and flatten waves at Eastbourne by a third.
But CentrePort chief executive Derek Nind said without it Wellington would not keep up with new, larger ships set to arrive soon in this country.
CentrePort, which is owned by the Greater Wellington and Horizons regional councils, can take ships that carry the equivalent of about 4500 standard containers.
But with the new channel, Wellington will be able to handle ships that can carry the equivalent of 6000 containers.
Nind said CentrePort planned to lodge its resource consent in June to Greater Wellington Regional Council, and hoped to have the process completed in about nine months.
Ports in Otago and Tauranga have already won consent and started work on dredging their harbours to allow larger ships.
Wellington’s port could be home to many more containers if CentrePort deepens the harbour entrance.
Nind would not put a dollar figure on economic benefits for the work, but said it was necessary for the port’s future.
The work would take place over the Waiwhetu aquifer, and was expected to have an affect on the underground water supply used for the Wellington region.
Environmental impact reports commissioned by CentrePort said the effect would be negligible.
Eastbourne Community Board chair Virginia Horrocks said the community was still getting to grips with what the proposal meant for people there.
“There will be a fairly major affect on our beaches.”
There was expected to be about a 30 per cent reduction in wave height, which would impact on Eastbourne’s beach recreation, she said.
“It’s interesting how many people come to Eastbourne, particularly in a southerly, and there are various times of the year when our beach is a fantastic place to surf.”
CentrePort would also need to deepen the harbour around the Thorndon Container Wharf, with about 270,000 cubic metres of sediment dug out and dropped nearby.
Jim Mikoz, president of the Wellington Recreational Marine Fishers Association, said while the work was needed for the port, he questioned why the sediment would be dumped off Fitzroy Bay.
He believed large quantities would wash straight back into the harbour entrance.
The project is open for public feedback until May 27 with a series of open days starting at Te Wharewaka o Poneke in central Wellington from 10 am to 3pm, on Saturday.
HOW WILL IT BE DONE?
* CentrePort may undertake the deepening works in one go or in a series of smaller stages.
* The entire dredge in one go with a larger vessel would take about 18 weeks, while a smaller vessel it would take about 90 weeks.
Source: stuff.co.nz
