Out-of-hours use of Canberra's Aqua Park has raised concern after some sections were deflated and sunk and others whipped by fierce winds out into deeper areas of the Lake Burley Griffin.
People who pay to use the popular park at Tarcoola Reach during its opening hours are given a life jacket and are under supervision of a lifeguard.
"We know people are using the park unauthorised and out of hours and while we don't like it happening, our biggest concern is that someone may be injured or worse," co-owner Will Yeap said.
"One of the largest sections was deflated and sunk, and others were released from their anchors and blew out into the lake."
A security guard was hired to dissuade people from out-of-hours use but could do little to prevent it happening and entreaties to police asking them to swing a patrol past late in the evening were unsuccessful.
The park is not permitted under National Capital Authority regulations to install a CCTV camera but Mr Yeap said he would re-apply as this was one of the few security options remaining to them.
Despite the operational losses incurred out of hours which Mr Yeap said have run into thousands of dollars, the trial to run the Aqua Park has been a success with around 15,000 people using it since opening in November.
"We had to close for about two weeks during the season because of smoke and storm water run-off in the lake but aside from that, it has been quite a success," he said.