Sewage has flowed into Lake Taupō after a tangle of wet wipes and sanitary items caused pipes to block up on Wednesday afternoon.
The blockage caused sewage to flow into Two Mile Bay near the boat ramp, Taupō District Council says, and locals are now being warned not to swim in the area.
The council says contractors have moved to contain the overflow, and have removed the items that caused the pipes to become congested.
The blockage comes just weeks after Civil Defence director Sarah Stuart-Black urged Kiwis to be more vigilant about what they do with antibacterial wipes during the COVID-19 crisis.
Before the coronavirus crisis, Watercare told Newshub Kiwis flush 700 tonnes of wet wipes - 53 million individual wipes, the majority of which contain plastic - down the toilet each year.
But as people have become more vigilant about hygiene during the coronavirus outbreak, the use of wet wipes has markedly increased, Stuart-Black says - leading to greater risk of blockages.
"They are a major problem for [the] council's wastewater and treatment plants, and sewerage systems," she told media in March. "The bottom line is: please always put wet wipes in the rubbish and not the toilet."
Kevin Strongman, Taupō District Council's group manager of operational services, says the latest sewage overflow is a timely reminder to be mindful of what you are flushing.
"Thank you to the vast majority of the community who are following the 'three Ps rule', ensuring only pee, poo and (toilet) paper are being flushed," he said.
"Anything else has the potential to block our sewer pipes and cause overflows into our beautiful lake."
Water samples were collected from Two Mile Bay on Wednesday, and signs are up advising the community to avoid swimming there until further notice.
Sewage pipes blockages cost taxpayers millions of dollars each year. They are predominantly caused by antibacterial wipes and grease, and are known as 'fatbergs'.
Antibacterial wipes typically contain plastic, but manufacturers aren't required to list the ingredients on the packet, meaning many Kiwis don't understand the damage they are doing to New Zealand's sewage system by flushing them.
