Horizons Regional Council has recommended people stay out of freshwater and coastal swimming holes this weekend following a week of heavy rain in the region.
Improved weather is forecast for parts of the region this weekend, which meant many swimmers could be heading to their favourite swimming holes.
However, due to recent heavy rainfall in the Manawatū-Whanganui region, Horizons recommended people stay out of freshwater and coastal swim spots for at least the next three days.
Horizons environmental monitoring scientist Kelly Le Quesne said coastal and river sites are unsuitable for swimming because flooding events increase contamination in water.
"Faecal contamination in water is measured by testing for E.coli in our freshwater sites and Enterococci in our coastal sites. These indicator bacteria can increase significantly with high rainfall as contaminants from urban and rural settings are washed into waterways.
"Horizons monitors 80 swim spots across the region on a weekly basis for water quality at these sites however, it is also important the public treat all floodwater as contaminated.