Horizons monitor more than 80 swim spots across the region, and updates to test results are due later in the week.
Le Quesne advised people to check the Land Air Water Aotearoa (Lawa) website to see how suitable swimming is at monitored sites.
“It is important, however, that people still check the water, even if Lawa shows it is suitable for swimming.”
She also said it’s important to remember things might have changed underwater since you last swam, to check for large debris and to be mindful of the fact that rivers and beach currents can be unpredictable and deceptively strong.
“Do not enter the water alone, closely supervise children and keep out of the water if you are not a confident swimmer,” she said.
Horizons has been monitoring the weather since the weekend, and reminded people to stay out of floodwater as it can contain contaminants like faecal matter and other hazardous materials.
“People should avoid all floodwater, including [by] not driving vehicles into floodwater. Put safety first and do not take any chances,” Le Quesne said.