The Wanganui Aquatic Centre started the new year off with a family day celebration offering gold coin entry and free rides on the hydroslide.
Manager Warren Webber said there were six lifeguards on duty and the staff were expecting crowds to arrive later in the day when some people had slept off their new year celebrations.
"People are likely to feel like a refreshing swim after a late night and we are open until 6 o'clock," he said.
It was just another day in the pool for the Koro whanau who have been spending hours at the centre each day since the hot weather kicked in.
Teherureu Koro, 15, was making his little cousins laugh as he tossed them over his shoulder and 2-year-old Dallas enjoyed a ride around the pool in dad Steelie Koro's arms.
Lifeguards Liam O'Leary and Christian Conder, both 19, said they are enjoying working their third season at the Aquatic Centre.
"It's a good summer job and I look forward to coming back each year," said Liam.
The trust overseeing the pool has been helped with a grant from the Whanganui Community Foundation which allows it to keep admission prices down and also provide some shade cloths.
Preschoolers and spectators get in for free, children are $2.50, adults $3.50, students and gold card holders $3. A swim and hydroslide pass costs $4 for children and $5 for adults.
Concession tickets are available, giving children 10 swims for $20 and adults 10 swims for $30.
Liam said admission fees were being kept to a minimum to attract as many people as they could.
The centre will be open every day during summer and hours are: Monday to Thursday, 10am to 6pm, Friday to Sunday, 10am to 5pm and public holidays, 12 noon to 5pm.