Tauranga City Council says it's taken the drastic step of evacuating homes, in order to save lives.

People living at a Tauranga subdivision could be out of their new homes for more than a week, because of to slip fears as Cyclone Hola moves in.

Twenty-one houses at The Lakes, 13 of which were occupied, have been evacuated.

Accommodation has been arranged for residents, who've been told they'll be out for at least a week.

City Council Chief Garry Poole says flaws have been found in a retaining wall, which could fail if cyclone Hola hits the Bay of Plenty.

"If the wall was to go it would have serious consequences because it is likely that some of the houses would go. The geotech engineer has indicated to us that there is a serious issue in the context of potential loss of life."

Poole says there's not enough time to reinforce the wall before the storm.

He says it is now a case of waiting to see what impact the incoming storm has.

"Next week we will undertake a geotech survey, and if they are good they will be allowed to go back straight away and if they are not we will reassess the situation and have a conversation with the residents."