Rainfall of up to seven millimeters an hour in Christchurch has caused the Heathcote River to burst its banks.
The heavy downpour began shortly after midday on Friday.
The river has risen above its banks for the second time since August at a flood-prone area weakened by recent earthquakes.
The Christchurch City Council contractors are monitoring water levels, but expect them to recede quickly as the tide goes out.
