A section of the Manawatu River is now too dangerous for users, because of the instability of the land above it.
Horizons Regional Council has closed the stretch of Manawatu River 200m either side of the Manawatu Gorge slip, until the land above is stable.
The closure follows discussions with the New Zealand Transport Authority (NZTA) and has been put in place to ensure the safety of all river users.
Habourmaster Evan Lloyd said there was potential for debris dislodged by the earthworks to fall, putting commercial and recreational river users at risk.
"NZTA will take precautions to warn users and stop work if anyone does enter the danger zone, but it is important that people remain vigilant and stay away from the area until further notice," he said.