The Waitaki District Council is exploring options for dredging Oamaru Harbour, but in the meantime is trying to ease pressure by using diggers to deepen the entrance.
Private boat owners and commercial fishermen who pay mooring and berthing fees will get a discount until the situation improves.
The council this year trialled using an excavator with a long-reach arm, specially imported by Rooney Earthmoving, but it was not wholly successful.
Over the past few days, two diggers have been working at the harbour entrance - one building a platform for the other to use the long arm to remove material.
Harbour sub-committee chairman Gary Kircher said on Wednesday long-term solutions were being explored.
Before any could be finalised, the council needed to obtain a new resource consent from the Otago Regional Council for the dredging.
One option being considered was for the council to buy and own a pontoon.
The pontoon would hold an excavator which would dig out the harbour entrance.
The material would be pumped either out to the sea or to the beach just north of the land end of Holmes Wharf, to help reduce coastal erosion.
The shallow entrance has been criticised by private boat owners and commercial fishermen, who say it is unsafe.
Some fishermen have threatened to relocate their boats.
Corporate services group manager Stephen Halliwell said attempts had been made to find a solution to dredge the harbour in a more cost-effective and efficient manner.
"The council, over the past decade or more, has found dredging the harbour very challenging," he said.
The harbour entrance was last dredged in 2004.
The preferred option to get a 4m-deep channel was to use the pontoon with the excavator.
"We should continue to work on funding a barge solution to establish a long-term, sustainable solution to keeping the harbour entrance at our proposed depth," Mr Halliwell said.
