Police say 20 people caught driving legally drunk the Beach Hop over the weeked is "unacceptable".

Despite several fines being issued, police say the majority of people were well behaved at the Whangamatā Beach Hop, which returned to its traditional March time slot this weekend.

"The event was well run, and the vast majority of participants were well behaved and enjoyed a great weekend," says Acting Senior Sergeant Niwha Jones.

"Unfortunately, 74 infringement notices issued for breaches of the liquor ban were issued, and 12 people were arrested on Saturday night for various disorder offences."

Twenty drivers were processed for excess breath alcohol.

"This is unacceptable and disappointing for Police," says Acting Senior Sergeant Niwha Jones.

"We know that intoxication increases the chance of causing harm on the road, and despite a strong Police presence some motorists still decided to take that risk."