The event ties in with the official end of the surf life saving patrol season which this summer has seen a focus on education about rips and what people should do if they are caught in one (relax and float, raise your hand, ride the rip).
"Lifeguards will take people in small groups and show them the dangers of Kai Iwi Beach," Fore said.
"They'll show people where the safe places are to swim and how the tides work. It's a good way to wrap up the season."
There will also be a surf life saving demonstration with rescue boats and surf life saving sports activities.
People are invited to bring accessories to decorate their masterpiece in the sandcastle building competition which starts at 12 noon and is open to families, children, friends and individuals.
"It will be a castle theme so it could be a Barbie castle, Game of Thrones castle - whatever they like," Fore said.
The sandcastles will be judged at 2.30pm, giving entrants time to take a break to participate in the beach dig at 1pm.
"We'll have more than 100 tokens for prizes buried in the sand," Fore said.
"The dig is for adults and kids."
A sausage sizzle will be available and people are encouraged to bring picnics.
The programme is:
12 noon Build a sandcastle competition
1pm Beach dig (gold coin entry)
1.30pm Surf life saving sports
2.15pm Surf life saving demonstration
2.30pm Guided beach safety tours; judging of sandcastle competition
