Residents say a new subdivision development is to blame after flooding affected two Albany cul-de-sacs, but the site manager will not acknowledge water was flowing from its pipe.
Auckland council said water engineers would investigate the drains, including at the Verdant Lane development at the end of Samuels Lane.
Culs-de-sac on Samuels Lane and Suckling's Lane became pools today, with water reaching waist height in places after 52mm of rain fell within an hour north of Auckland this morning.
Sophie Xu said she and her mother-in-law felt devastated when their house flooded, damaging skirting, carpets, vanities, a couch and a laptop.
She said theirs was the only house on the lane that was sodden, and they were thankful to their neighbours who helped with the clean-up.
"I came back home and [there were] people around the house [trying] to brush the water out," she said.
Neighbour Peter Berry, who helped the family, said there was a huge amount of water but it was not just coming from the sky.
"There is a sewer line that runs from the development right through the middle of the road ... all the stormwater came through the sewer line and then bubbled up through the road," he said.
"It shouldn't come through that because it was stormwater and it was all clay as well so it was very dirty."
It would not comment further until the investigation was complete, but Watercare said it discovered a wastewater pipe had been laid by the developer.
Stormwater was using the pipe as a pathway through the soil. Contractors were about to cap the pipe to prevent further issues as a goodwill gesture, Watercare said.
The developer - Schick Vertical - and site manager Simon Gibbs would only say the development was not connected to the sewer system.
Mr Gibbs would not acknowledge whether water was coming out of the pipe which belonged to the site.
Meanwhile, on nearby Suckling's Lane, more residents were trying to mop up the mess.
They also said it was caused by the development.
A pool of water also settled in their cul-de-sac in less than half an hour, local resident Mark Nielsen said.
"To the point where the wheelie bins were floating around the street and it was up to our waist within about less than probably five or six minutes."
He said it was a close shave.
"We're very, very lucky that none of us have actually had [any flooding] because basically it's come within millimetres of coming into the house."
The deluge also put a dampener on his 17-year-old daughter Phoebe's day.
"I came out and my car was like fully submerged, like the exhaust pipe and everything, and it's my first car as well," she said.
"It's all flooded inside so I'm just trying to empty it out.
"I guess at least it's not our house underwater, that's the main thing."