Port Otago has stopped using its offshore spoil dumping site - 6km off Taiaroa Head - after realising it had not completed one of several baseline studies, as required under its resource consent.
The port company is just weeks away from reaching its target depth of 13.5m in deepening its shipping channel, which runs for about 13km between Port Chalmers and Taiaroa Head.
Port Otago chief executive Geoff Plunket said the consenting issue at the offshore site was "purely a technical issue'' and there was no environmental effect.
To reach a consistent 13.5m channel depth, Mr Plunket said there was still some "tidying up of some high spots still to be removed''.
Instead of offshore spoil-dumping, existing inshore disposal sites were being used.
Mr Plunket said all consenting conditions at those sites were being met.
Resource consents for Port Otago's Next Generation lower harbour dredging programme were granted in February last year and the port company was required to do several baseline studies before dredging and disposal at the offshore site could commence.
"Subsequently it was discovered that one of the baseline studies had not been completed and as a result, Port Otago has stopped using the [offshore disposal] site,'' Mr Plunket said yesterday.
The channel is being deepened and widened to accommodate larger container ships.
Mr Plunket said Port Otago had consulted with all interested parties before using the offshore disposal site and the required Environment Management Plan was prepared.
He said the relevant study was being completed and the use of the offshore site was expected to resume by late March.
While Port Otago has consent to remove 7.2million cubic metres of spoil, in its dredging programme to date it had removed and disposed of 114,000cu m
to the offshore site by late December.
Mr Plunket said monitoring at the offshore site had indicated it "performed in line with expectations''.
Next month, Port Otago's dredge New Era will have its five-yearly survey and maintenance.
It was expected back in operation from late March, Mr Plunket said.
