Thousands of people plan to join a floating party on the Bow River, raising the concerns of Calgary police.

More than 7,400 people have RSVP'd on Facebook for a “River Rave” on July 5, launching from Bowness Park. Plans call for a raft blasting Canadian electronic music, with other rafters floating behind.

Organizer James Katalyst said last year’s float attracted fewer than 100 people, but this year’s will likely be a much larger event, although he expects only a fraction of the people who RSVP'd to attend.

“All we are doing is inviting people to show up at a certain time and we will have a raft with some speakers on it. That’s the whole organization right there,” he said.

Katalyst didn’t contact emergency officials about the event, but posted the rules and restrictions about rafting in Calgary on the Facebook page.

“We definitely want people to be safe,” he said.

Calgary police Sgt. Kevin Knight of the marine unit said he’s aware of the event.

“The river has changed dramatically since the floods of 2013. The flow of the water, the pathways through the water that people knew before, are not the same this year. There is always the potential of something to go wrong when you have large amounts of people like that.”