Plans for a new £200,000 jetty near historic Conwy Castle have divided harbour users.
Proposals to replace the existing timber jetty had to be scrapped because of costs, and an alternative site has been identified near Conwy bridge.
An online petition supports the scheme, with some fishermen say they need 24-hour access to the harbour.
But objectors say the new spot is unsuitable because of safety and issues over access for disabled people.
A report is going before Conwy councillors later.
Sara Allardice, a town councillor and a member of the Harbour Advisory Committee (HAC), said there was concern about the new jetty not being "disabled friendly", and that it would not be safe for all users.
"It is in a more dangerous area than it is now, as the tidal flow is very fast at that end by the bridge," she said.
Ms Allardice added that at low tide the gradient of the new jetty would be too steep for wheelchair users.
"The jetty isn't just for boat users," she said.
"The commercial users of the quay and tourism [are] very important to our county and many people currently use the jetty, down to the the children who enjoy crabbing," she added.
The council says the location of the new jetty, which will be accessible in all tides, also has to remain free from silting in the long term.
With only £200,000 available for the work, replacing the current structure is unviable because of a cost of £770,000.
Moving it off the main quay wall was also dismissed because that would cost £480,000.
Using the existing fuel supply facility near the bridge is seen as the best alternative with a projected cost of £210,000, the report adds.
An online petition has 81 signatures from people who support the council's new plan.
Harbour users such as fisherman Andrew Armitage, who operates the trawler Tenacity, said having 24-hour access to the harbour was vital.
"A lot more fishing boats are coming back here," he said.
"What we need is to get the catch unloaded in the best condition, and to sit out there for seven to eight hours as the tide turns to unload is not very good really," he added.
Colin Boswell Williams, who has a pleasure boat in the harbour, said a deep water jetty would allow boat users to get ashore at any time of the day.
Joan Vaughan, the Conwy council cabinet member for infrastructure, who is also a Conwy county councillor, said the present jetty was silting up because of a change in the tide patterns.
She acknowledeged that there might be some issues for less able bodied users but everything would be done to mitigate any issues, she added.
She said the safety issue was "paramount".