Western Bay of Plenty District Council civil defence controller Peter Watson said floodwaters receded quickly on Monday afternoon, and teams were taking a closer look at the affected properties.
“Our Rapid Building Unit guys are going to assess the pensioner units and any other buildings that need to be assessed as to whether they are habitable at the moment”.
He said a welfare team would also check in with each person displaced by the flood and work out their long-term needs.
The pensioner housing on Beach Rd had been one of the worst-hit areas, with 11 out of the 19 units flooded.
Water had been up to the windowsills so there was likely to be “a lot of mess” inside, he said.
He said it appeared to be a very localised downpour which caught everyone by surprise.
“A lot of locals said they had never experienced [a downpour] like that before. It’s pretty hard to predict the weather to that level in this country with the radar systems we have.”
Despite the orange weather warning, other areas such as Katikati had more usual levels of heavy rain.
The wastewater system was working on backup generators after the power was cut and would be checked today, and roads had had tarsal and kerbing channels ripped away, Watson said.
Katikati-Waihī ward councillor Allan Sole said emergency services teams had been needed to help get people out.
“There were people there who were vulnerable and were having to be evacuated in a fairly deep pool of water.”
He said the flats were right beside a stream and there was nowhere for the water to go.
Sole told RNZ the streets and homes flooded on Monday, including the pensioner units, had been hit before.
Ten years ago there was a major flood in the same area and the council then allowed people to raise their homes above what they thought the water level would be, he said.
“But of course, the lower areas or their garages and their sections would still have water on them”.
He said much of Waihī Beach was low-lying and houses had been built on swampland.
Western Bay of Plenty mayor James Denyer went to Waihī Beach on Monday night and told Morning Report the elder housing units were flooded to chest height, roads were “torn up” and fences pushed over. He said 27 people were evacuated.
Stormwater infrastructure and ponds were unable to cope with the up to 120mm of rain locals said fell in two hours, he said.
“There are some chronic stormwater issues in Waihī Beach dating back to how the settlement was first put together.”