How it works
Keeping you informed
With so much going on in the harbour we’re sure there will be plenty of questions, and we’re here to answer them. Have a browse of the Q&A below. If there’s something new you’d like to ask, please fill out the form below and we’ll get back to you with an answer.
Wed 17 Apr
How are the piles driven in, I sit at home with my Grandson watching but haven't been able to figure out how it is done, I find it very fascinating and the noise doesn't bother us at all, Thanks, Rosa.
Thank you for your question.
First we bring the piles across the Inner Harbour in a purpose built barge. The crane then picks up each pile and places it in the pile gate or guide. The is a frame which ensure the piles are in the right place and held vertically during the pile driving.
The piles are driven in using two methods. Initially we use a 'vibro method', this is a green piece of equipment that sits on-top of the pile. Basically this method shakes the pile into the ground, but can only be used where the ground is soft or for about the first 10-15m of the pile.
The main method used to drive the piles is a 'hydraulic hammer', which is the more noisy method. This is the large cylindrical yellow part you may see on top of the pile. Within this part is a large weight which is repeated dropped onto the pile, hammering it into the ground. We keep dropping the weight until the pile is driven fully in, or the pile has the required strength.
As we cannot lift the full pile length (about 70m long), we have to drive each pile in parts. Once the first section is driven in, we weld the next section in place. The welds take some time to do as they have to be very carefully done, you might notice these periods as the piling ceases during this time.
Mon 04 Feb
My neighbours and I have been watching the removal of the small lighthouse (opp the rec ground). We hope this will end up in a public space in Lyttelton somewhere, the marina maybe. Please could you tell us what happens with it now? Thanks
The small white structure was formerly the 'centre lead' which helped ships know where the centre of the channel was.
Due to the channel being deepened and widened, we needed new navigation aids. As a result, the old aids, including the white centre lead, had to be removed.
As LPC already has a similar structure in storage (the old lighthouse from the Eastern Mole), we couldn't keep the one you were asking about. Thankfully a keen local sailor saw a use for it, and it has been passed on to him.
LPC has yet to decide where the lighthouse we have stored will go, Te Ana sounds like an idea worth looking into though. Thanks for the idea!
Wed 21 Nov
Are you going to keep all the buoys providing turbidity and water temperature information after the dredge has gone? Ie are these buoys and their real time info permanent
As we still have some minor dredging work for the reclamation and cruise berth, the buoys will stay for another 6-10 months. So you will be able to keep an eye on the water quality and temperature for a while yet.
Mon 19 Nov
What is going on just beyond Rapapa Island -towards the Heads- some sort of piling??? for what?? A barge and crane putting down pile/s
The barge and crane are starting to put in new navigation aids for the deeper, wider and longer shipping channel. Keep an eye out for an upcoming blog story on what they are and how they work.
Wed 17 Oct
What sort of fuel does the dredge use that it has to go to Wellington to get it?
The Fairway can use a range of marine fuel oil, unfortunately there isn't sufficient volumes of those fuel available in Lyttelton. So she had to whip up to Wellington for refuelling.
Fri 14 Sep
Hi, What's the small boat called " Capricorn Alpha"
doing ? Cheers Bruce
The Capricorn Alpha is a 'sweep tug' which is working on the Channel Deepening Project. She tows a large blade along the sea floor to even out the troughs and humps left by the bigger dredge. She also helps scrape off the shallower parts that the big dredge cannot reach.
Wed 12 Sep
Fairway dredge is on route to wellington tonight, any reason why.
Good spotting! Yes, she is off to Wellington to refuel as there is not enough fuel available in Lyttelton. She will be back on Thursday.
Wed 05 Sep
What experts are you working with?
The following experts are involved in the marine mammal aspects of the cruise berth:
Scope of work
Dr Deanna Clements Cawthron Institute Marine Mammals. Dr Matt Pine Styles Group Marine Mammal Acoustician – acoustic instrumentation, data processing and interpretation. Darran Humpheson AECOM Underwater Acoustics – modelling of piling noise.
Dr Leonie Andersen/
Dr James Saddler
Vision Environment Ltd Water Quality Monitoring and installation/maintenance of
marine mammal instruments.