The Manawatu River has peaked after heavy rains but authorities will keep a major floodgate system open until late on Friday afternoon.
The Manawatu-Wanganui Regional Council's incident controller says the Moutoa floodgates are open on Thursday evening.
Allan Cook says the river remains high and there are still some patches of heavy rain.
Other rivers are also rising, but are not predicted to cause concern overnight on Thursday.
There is flooding across some roads and drivers should take care.
State Highway 56 is closed at Opiki, as is the road into Scott's Ferry.