A crew will be on standby to open the Manawatu River floodgates as the swollen river peaks on Friday night.
Heavy rain in Tararua and Manawatu has eased, however, rivers in the region are still running at higher than usual levels.
Horizons Regional Council says farmers in the Moutoa floodway, between Foxton and Shannon, have been warned to move stock and drop fences in preparation for a possible opening of the floodgates.
A Horizons spokeswoman told NZ Newswire a crew will be on standby at the Moutoa floodgates from early Friday evening, ready to open them if needed.
The river is expected to peak at Moutoa about midnight.
Earlier on Friday, the Manawatu River was running almost seven metres higher than normal through the Manawatu Gorge.
State Highway 3 through the Manawatu Gorge was closed on Thursday night after some of the slip material that supported the temporary road was eroded by the rising river.
It's expected the road, which was partially reopened in May 31, will be closed for six weeks.
State Highway 56, near Shannon, has also been closed on Friday, with the Opiki floodway underwater.
Horizons says it has been monitoring the situation and it has no concerns about river levels in the rest of the region.
NZN