Swimmers are being advised to stay out of the water at Raumai Reserve after a rock fall from a cliff along the Pohangina River.
Horizons Regional Council was alerted to the rock fall on Sunday morning. The Manawatu District Council is installing signs in the area encouraging caution.
Nobody was hurt in the rock fall.
"We would advise people against swimming at Raumai Reserve for the time being. If people are thinking of going for a swim, please check for any warning signs," Manawatu council community services group manager Brent Limmer said.
Horizons chief executive Michael McCartney was among the regional council staff who responded to the rock fall. He lives nearby.
"Luckily, no swimmers were hurt but it is a reminder of the need to take care when swimming in any river or stream," he said.
"We have some wonderful swimming holes in our region and we encourage people to get out and enjoy themselves this summer.
"At the same time, we need to be aware of things like sunken logs, rocks and cliffs to make sure we stay safe."
Horizons conducts weekly water quality monitoring at 16 popular swimming spots throughout the region from November to April every year.
Another 29 sites, including the Pohangina, Kahuterawa, Tokomaru and Oroua rivers have a permanent grading system in place.
Swimmers are encouraged to use the following rules of thumb: If the water looks clean and clear and it's a sunny day it should be fine for swimming; after a period of rain wait three rain-free days before using river swimming spots.
Raumai Reserve is about 6 kilometres downstream from where three children were killed in a cliff collapse while they were swimming in the Pohangina River in 2006.
- Manawatu Standard
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