"Then he started driving along the beach. Another boat towing two biscuits was nearly taken out."
Shortly after, the boatie's wake washed two children off a ski biscuit. The boat then allegedly struck the children's parents after they reached the shore.
Hungerford saw a report about the accident in last weekend's Herald on Sunday and contacted the newspaper.
He said he was told the 25-year-old boatie was a Waikato dairy farmer, though Hungerford did not know his name.
Waikato Regional Council navigation safety programme manager Nicole Botherway said an investigation into the day's events was still underway.
The boatie could face charges under Section 65 of the Maritime Transport Act, which makes "dangerous activity" involving boats an offence, regardless of whether injury or damage occurs.
It cost Hungerford more than $500 to fix the boat. "We didn't really give a stuff about the boat at the time. We left before I got angry."
Police spokeswoman Victoria Evans could not comment on the incident but said it is an offence to operate a boat in a manner which causes unnecessary danger or risk to any other person or to any property, irrespective of whether or not in fact any injury or damage occurs.
"Police can and do prosecute people under this Act, as can Maritime New Zealand," she said.
"Local councils can issue infringement notices to boaties for excess speed, not having an observer and not having lights on at night."
Six weeks ago, coroner Carla na Nagara reminded the public of the "very real risk of being drunk on boats" when she found Porirua resident Patrick Rosson died after falling overboard while urinating off a boat. Rosson was almost three times the legal blood alcohol limit for drivers.