Beach-goers are sceptical about their favourite beaches being deemed unsafe on a new Auckland Council website.
Safeswim, launched on November 4, provides a three-day forecast covering 84 beaches and eight freshwater locations around Auckland, designed to encourage swimmers to check before they swim.
On Wednesday morning, November 8, the website advised both Takapuna and Torbay beaches would be unsafe to swim in, after heavy rain overnight.
However, on a Torbay community Facebook page, resident comments switched between scoffing at the idea their favourite beach was unswimmable and saying it had always been “smelly”.
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“That is really silly,” said Hannah Allen on the page. “Many people swim there including myself – it’s not dangerous at all.”
They also questioned how reliable a predicted warning could be and whether this meant the end of physical testing.
“Personally, I’d trust my eye balls over the council’s computer models. I hope they’re still testing also,” Mark Mackay added.
The forecasting system, developed by Auckland Council and Watercare, predicts faecal-indicating bacteria through the relationship between rainfall, wind, tide and bacteria.
The site describes water quality in three levels: green = low risk, yellow = fair, red = alert. According to national guidelines, “yellow” is the minimum acceptable state for swimming, whereas swimming is not advised on “red” beaches.
These labels can fluctuate between morning, afternoon and evening, depending on environmental factors.
Healthy Waters specialist Kris Fordham said physical weekly or monthly testing would continue, depending on the beach.
The website’s data works similarly to weather forecasts, Fordham said.
“Rain is a key driver of water quality but other factors are relevant: wind, tide, sunlight and proximity to known overflow points in the wastewater network.”
The system also uses real-time data from sensors on the Watercare network. Therefore, unexpected overflows and blockages can update the website as required, he added.
Auckland Council has always warned people not to swim 72 hours after heavy rainfall.
However, after heavy rain, thanks to “high-energy water flow”, North Shore beaches are clear of contamination in a few tides, marine biologist Simon West said.
North Shore ward councillor Chris Darby said the results were likely to alarm many beach-goers but there was no hiding from the truth that we have much to do to improve water quality.
Along with water quality, Safeswim also provides lifeguard hours and reports other hazards, such as rips, unsafe cliffs, boating areas strong winds, shallow water and sudden drops.
Check before you swim at safeswim.org.nz