Tauranga city has spent $14,000 organising the party to celebrate the new waterfront this weekend.
A council spokeswoman said support from sponsors More FM and Downer, and partnership with Downtown Tauranga meant the city was able to deliver an event worth about $51,000 for much less.
But the new waterfront by The Strand continues to be controversial since the city first announced it would remove 169 carparks from what was the reclamation car park to make way for a grassed area.
Publicity about the party has sparked strong debate online at www.bayofplentytimes.co.nz.
The website was yesterday inundated with comments for and against the new waterfront.
Sunday's event will be free and include 2012 Olympic gold medallists Eric Murray and Hamish Bond, live entertainment, fireworks, bike trials, a metal maze, The Little Big Markets, Pirates of the Pacific theatre production, and Hairy Maclary activities.
Musician Luke Thompson will head the entertainment line-up of Lydia Cole and newly-formed band Oh Mary, which will perform their first gig at the event.
Thompson has performed at the Edgewater Fan on The Strand before and said having more space for a larger audience would be great for future music performances.
Crown and Badger and Steakout owner Colin Milne, who experienced a significant loss of trade since the removal of the car parks, said he had yet to be impressed by the new waterfront area across the road from both businesses.
''I've still got a bit of an open mind but so far it's had a negative impact on us,'' Mr Milne said.
Mayor Stuart Crosby said the waterfront redevelopment would create a dynamic open space in the city centre that could be used for a whole range of activities.
Little Big Markets owner Rachelle Duffy said the 50 stalls would range from vintage clothing to food.
Activities will also be on offer for children, including face painting and a treasure hunt.
The Spring Street Parking Building will be free and open for the day. There will be no parking on the waterfront.
■ If the weather is wet the opening celebration will be postponed until Sunday, September 30. Listen to More FM for postponement details.