More than 20,000 boats were registered in Lake Macquarie and about 50,000 in the Hunter, figures that were growing about 4 per cent a year, according to studies done for planned marinas.

More than 100,000 Hunter people had boat licences and that figure was growing at about 3.2 per cent a year.

Registrations of large power boats and sailing vessels have surged, generating plans for a new marina and two expanded marinas in Lake Macquarie.

The NSW Government is assessing the three plans under its controversial Part 3A planning powers.

Marmong Point Marina, in north-west Lake Macquarie, is planning to expand from 160 to 245 wet berths with a new dry storage area of 110 berths, while Lake Macquarie Yacht Club, at Belmont, plans to increase its marina berths from 83 to 147.

A new 308-berth marina is planned at Trinity Point, Morisset Park, in south-west Lake Macquarie.

A report accompanying the Trinity Point marina plan said there was strong demand for "boating access and facilities including marina berths" in the Hunter.

"Demand has been driven by a more affluent society requiring improved and modern marina facilities for the storage of larger vessels," it said.

The report said marina berths had increased over the past 20 years in Port Stephens and Newcastle Harbour, but "there has been almost no growth in marina berth infrastructure in Lake Macquarie".

"Surveys show most marinas in Lake Macquarie have waiting lists. There is likely to be a strong latent demand for modern marina berthing in Lake Macquarie," it said.

The report said growth in the number of swing moorings now exceeded 2.5 per cent a year.

"Some mooring areas are now closed with no further applications accepted. It is likely that saturation point will be reached at some point, as individual mooring areas reach their limits and are closed," it said. "As this occurs, there will be an increased demand for marinas."