Visitors are being turned away from Coochiemudlo Island because of the restrictive parking situation on the mainland.
Coochimudlo Island Progress Association says the situation is 'getting out of hand'.
She believes the restructured parking area has a poor layout that does not optimise the parking area, with too heavy a consideration for boats and trailers.
The president said: "The car park at the jetty is for cars with boat trailers on them every weekend, no matter what the weather .Some days there is not a single car and trailer there.
"This is having a big impact on weekend trade, as we have photos etc. of cars being booked for parking there, even though there are no trailers or people boating or fishing."
Gwenda Bryant added: "Many people who wanted to come for our recent Markets on Flinder's Day, turned away and went elsewhere.
"The situation is getting worse because parking contractors are excessively canvassing the area and putting a nail in the coffin of our tourism industry.
"We have met with various levels of council, with little or not result.
"It seems there is no common sense prevailing," the president said.
She added she is having an 'alternate layout' of the parking area prepared to present to council.
"We think far more cars can be accommodated with a more common sense approach.
"There is no recognition for people who want to make use of our tourism facilities for weekend stays.
"They are turned off when they return to their cars and discover their cars have been booked."
Gwenda Bryant believes a solution is possible, "but it needs goodwill from some areas of Redland City Council, she said.