Instead of charging $4 per user of the facility, hospital management will now collect a flat $55 booking fee per session for groups of up to 10 people.

For full groups of 10, this represents a per-user increase in price of about 38 per cent. Smaller groups will face a much higher increased cost burden.

Hospital general manager Denis Thomas said the new scheme had been worked out after consultation with the pool's major users as a way to improve its bottom line.

"There are three significant groups that use it in terms of sessions per week and they seem to be comfortable with the idea," he said.

"Even with six to eight people, it wasn't getting up to $10 per person."

Mr Thomas acknowledged the new fee structure disadvantaged individuals who used the pool independently of large groups and the hospital may look at alternative measures to better accommodate those users.

"One thing we'd look at, depending on utilisation, is whether there's capacity for certain times of the day for individual users and that would be a different rate," he said.

The fee structure won't be changed again during the remaining nine months of the review period, Mr Thomas said, while there is still no commitment from the hospital to maintain the facility beyond next March.

Public support for the pool remains strong, according to hydrotherapy pool advocate Karenne Connors, with a petition still circulating calling on the hospital to keep it having attracted more than 1500 signatures.

"They're saying keep the pool," she said.

"It's a public facility in a public hospital and I know it was (built) 20 years (ago) but there's $243,000 of community money in that pool and we must remember that."