Rain washes toxic algae from regions' rivers

The rain and dark clouds over the weekend had the silver lining of flushing toxic algae from the region's rivers.

"We expect that all rivers in the greater Wellington region are now free from toxic algae. That's certainly the case in Kapiti where the Otaki and Waikanae rivers flowed at around six times the flow required for flushing to occur," says Dr Mark Heath, Senior Environmental Scientist, Marine and Freshwater, Greater Wellington.

"High flows were also seen in the Hutt River and Wairarapa rivers and we are very confident that they are free from toxic algae."

Greater Wellington's water quality team will be out and about testing rives over the next couple of days, and Greater Wellington's Is it safe to swim? website will quickly be updated with new - and almost certainly positive - information.

"The only drawback of the rain is that it can also flush potentially harmful contaminants into rivers and harbours, such as e.coli, which is why we urge people not to swim for at least two days after rain."