Toxic algae is once again causing problems as the summer starts to take hold, and swimmers are urged to take care, especially at the Waipoua River in Wairarapa.

The advice is for people and dogs not to enter the Waipoua River from Paierau Rd to where it meets the Ruamahanga River. There is a severe toxic algal bloom in this area with detached mats building up at the river margins. Rain forecasted for Masterton over the next few days is unlikely to do much to help the situation.

The Pakuratahi River monitoring site at Kaitoke Regional Park has 20% cover and people are advised not to swim in this location.

The Hutt River is safe for swimming but toxic algae is starting to build up at some spots. Know what to look for and exercise caution.

Monitoring results from the Otaki and Waikanae rivers are pending and if any concerns are noted they will be shown on the “Is it safe to swim” website.

The algae grows on submerged river stones in a shiny brown/dark green to violet coating. It can also become unstable and detach, floating to the surface forming small brown/black mats at the water’s edge.

It is important to keep an eye on babies and toddlers who may put objects in their mouths. Seek emergency medical attention immediately if anyone in your group swallows toxic algae.

If yourself or others have been swimming in a river or lake and have any of the following symptoms: nausea, vomiting, numbness, tingling, muscle twitches, shaking, or weakness, see your doctor. Seek immediate medical attention for more serious symptoms such as breathing difficulties, convulsions or loss of consciousness.

Before you swim, keep yourself safe by finding out about toxic algae at http://www.gw.govt.nz/safeswim/.

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