Algae causes red water in Waikato lake - study

  • Breaking
  • 03/06/2014

By 3 News online staff

A new study has discovered why a Waikato lake's water has been appearing red.

The analysis identified that Monoraphidium algae has been causing the colour change in Lake Waikare's water and the Waikato Regional Council (WRC) believes it is not known to be toxic.

"What it does do is send a red colouration into the water around it. If enough of this is produced, the water can be very red," says WRC water scientist Bill Vant.

Mr Vant says the lake sampling indicates densities of the algae in April were nearly 300 times higher than results from last year and it is unclear why.

"Our understanding is that it can be quite common for algae to 'boom and bust' from time to time, sometimes for long periods," he says.

"That said, discolouration like this is very concerning and highlights the significant on-going environmental challenges faced by Lake Waikare and other shallow lakes in our region."

Mr Vant says a recent NIWA report on the Waikato River catchment for the Ministry for the Environment highlighted how there was no quick fix to these challenges.

"The council will continue to make sure regular monitoring of water quality at the lakes is done and appropriate information given to the District Health Board to ensure any appropriate public warning signs are erected."

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source: newshub archive