Western Bay of Plenty District Council is urging residents to keep fats, oils and grease out of sinks and drains this winter, warning that the build-up of so-called “fatbergs” is costing ratepayers thousands of dollars each year.

The reminder comes as colder weather and hearty home-cooked meals increase the risk of fats hardening inside pipes, contributing to blockages in the wastewater network.

Over the past year, wastewater overflows caused by blockages have cost the council more than $38,000, council said in a media release on its website.

Western Bay of Plenty District Council infrastructure general manager Brad Singh said winter was a particularly challenging time for wastewater systems.

“Winter is when we tend to cook more comfort food, but it’s also when fats and oils harden faster inside pipes, creating stubborn blockages that can lead to wastewater overflows,” Singh said.

“Fats, oils and grease should never be poured down the sink. Even small amounts can build up over time as they cool and stick to pipe walls.”

Fatbergs form when cooking fats solidify in pipes and combine with other debris, including wet wipes, paper towels and other items that are flushed down toilets.

Singh said wet wipes remained a major contributor to pipe blockages.

“Despite what the packaging says, so-called ‘flushable’ wipes don’t break down like toilet paper. They can combine with fats and other debris in the wastewater network, helping fatbergs grow.”

He said wastewater overflows were costly to clean up and could affect both communities and the environment.

“These overflows are messy, expensive to clean up and can impact both our communities and the environment, but the good news is they’re largely preventable.”

The council is encouraging residents to let fats, oils and grease cool before scraping or pouring them into a container and placing them in the rubbish. People are also advised to scrape food scraps into the bin before washing dishes, wipe greasy pots and pans with paper towels, and only flush the “three Ps”: pee, poo and toilet paper.

“This winter, enjoy your comfort food – just don’t feed the fatbergs,” Singh said.