'Very high risk' of illness by swimming after sewage overflow at Auckland bay

Wellington isn't the only city dealing with sewage in its water, with Aucklanders being warned there is a very high risk of getting ill by swimming at a central beach.

An alert on Auckland Council's SafeSwim website highlights that Home Bay, located near Herne Bay, currently has a "very high risk" water quality indicator.

This means that there is a "very high risk of illness from swimming" at the spot, due to "recent combined sewer overflow in this area".

The quality indicator at Home Bay, the only Auckland area with such a warning, was updated on Friday evening and is forecast to last until Sunday night.

Herne Bay is fine, however, with only a "low risk of illness", while there is a "high risk" further west at Coxs Bay and Meola Reef. These two spots are affected by levels of Faecal Indicator Bacteria that exceed national guidelines for swimming. 

Conditions were affected earlier this week when torrential rain and thunderstorms put pressure on wastewater networks.

Other beaches with a "high risk" warning include St Heliers, Point England, Green Bay, Titirangi beach, Milford South and Te Atatu Beach.

Wellington authorities are currently scrambling to deal with a wastewater network in the central business district collapsing. People are being told not to swim in the harbour.

SafeSwim is supported by a team of full-time water quality samplers who travel to 15-20 locations a day to collect samples. Typically, the worst time for water quality is after heavy rainfall as pollutants can get into the sea.

"While the programme is monitored on the ground by water samplers and surf lifesavers, what’s displayed on the website is made possible by millions of data points and calculations processed by predictive models," Auckland Council says.

"The Safeswim models have been calibrated to accurately predict from years of water sampling results."

The website can be found here.