Twenty members of the Port Kembla Chamber of Commerce are supporting the event by giving anyone who spends $20 in their businesses a chance to win a double pass to the water slide.

It comes just days after Destination Wollongong manager Mark Sleigh spoke about how significant the community response to the March 21 event had been.

"They have held eight [water slide] events around Australia over the last three months, and here over half the tickets sold in 15 minutes and we completely sold out in 12 hours," he said.

"They were by far the best ticket sales they experienced anywhere. And the support from the Port Kembla Chamber of Commerce has been amazing. We are really excited about what that day is going to bring."

Chamber member Tammy Mead, of Recycled and Pre-Loved, said when businesses in the suburb heard about the event they approached organiser Stuart Harris for 10 double passes to give away.

Mrs Mead said it was great marketing for the resurging shopping destination.

Businesses are so excited, staff at one bridal shop are thinking about sliding down Military Road in bridal gowns.

The chamber members are also giving passes to community groups to use to raise much needed funds.

But five or six double passes will be drawn on March 20, when the winning shoppers will be advised.

"It has all happened pretty quick," Mrs Mead said.

"We are so excited about how this will help the suburb."