Yesterday, fisherman Bill Harvey said the entrance was "extremely dangerous".
He was aware one boat had nearly tipped over twice in the past three weeks entering the harbour.
The Waitaki District Council has let a contract for the work to Rooney Earthmoving Ltd.
The council has been setting aside $100,000 a year for the past three years for dredging the harbour mouth.
Council corporate services manager Stephen Halliwell said a digger with an extended boom would be used instead of more traditional methods.
Rooney Earthmoving had imported the boom from Korea for the job.
The digger would be able to work in the shallows, reaching out to excavate the channel, he said.
Another boat user, Alex Wynne, was concerned about large rocks at the harbour entrance.
When the tide came in, the rocks could not be seen but they were not far below the surface, he said.
Mr Harvey, who has been fishing out of the harbour for many years, said he was unable to get his boat out until high tide.
The problems were due to nature and lack of maintenance.
Work on the harbour was costly and the council had limited money, he said.
