"It's pretty scary stuff. I just worried about his safety," the motorist said.
Kate Stevens and her daughter Lili, 9, live at one of the damaged houses. Ms Stevens said she had planned to be on the lawn yesterday morning, but met a friend for coffee instead.
"I was going to mow the lawns, but it was raining," she said. "We also park our cars on that lawn, but no one was here so I was pretty pleased we weren't. The timing could have been bad."
Lili said she often played on the front lawn - metres from where the truck ploughed through the property.
"I was surprised," she said. "I mainly play out there on the trampoline."
A spokesperson for the truck company, Flanders Waste, said the driver was okay and having tests in hospital to establish if a medical problem caused the crash.
Emergency services guided traffic past the scene while police undertook their investigations. The truck was later started and driven out from where it had come to rest.
Sergeant Paul Ormerod said there were no other vehicles involved.
"For some reason we are yet to ascertain, it has crossed the centre line into the southbound lane then moved back into his lane, then straight across into the fence there ... and just continued along."
A tree stopped the waste truck when it reached the fourth property, and the 32-year-old driver was taken to Hawke's Bay Hospital with minor injuries.
"Inquiries are continuing as to why he's crashed," Mr Ormerod said. "Alcohol does not appear to be a factor."
It was too early to say if a medical issue had been a factor in the crash, he said.
