The controversial bylaw is yet to be passed by Marlborough District Council, but in its present form it could see the Interislander face an extra levy of about $600,000 a year, the Marlborough Express reported.
Interislander spokesman Nigel Parry said as a result customers could have to pay a higher price for a Cook Strait ferry ticket.
The bylaw was ill-conceived and failed to address the dangers caused by recreational boaties, he said.
There was strong opposition to the proposal at a four-day hearing held in Blenheim.
Under the proposal, commercial operators would have to pay scaled safety fees and to instal an automatic identification system.
Destination Marlborough board member and co-owner of Portage Resort Hotel Dain Simpson said the whole of the Sounds and the Queen Charlotte Track was built up around a very efficient water-taxi service and a fee increase could see a drop in tourism.
