Monstrous discovery in Northland sewer prompts toilet warning

A small portion of the “rag monster” extracted from a Haruru sewage pumping station before it was collected by a sucker truck.

It’s the stuff of nightmares — vile-smelling monsters snaking through sewer pipes under our homes, causing blockages, stinking overflows and hefty bills for hard-pressed ratepayers.

Yet these monsters are created not by horror writers but by us, specifically our insistence on flushing things like disposable disinfectant wipes down toilets instead of popping them into the rubbish bin.

Northland’s latest “rag monster” was extracted, with great effort and unpleasantness, from a sewage pumping station at Haruru in the Bay of Islands.

The exact dimensions of the monster, consisting of rag-like material and congealed fat, are not known but it took three days to remove and was big enough to fill three sucker trucks.

Based on the size of a typical vacuum truck, its volume was at least 30 cubic metres and possibly as much as 50cu m.

The incident has prompted the Far North District Council to plead with residents, once again, to flush nothing but “the Three Ps” -pee, poo and (toilet) paper - down the loo.

A variety of items contribute to the growth of rag monsters but the key offenders are thought to be disinfectant wipes.

Many brands have been marketed as flushable in the past but unlike toilet paper they don’t break down. Instead they get caught in pumps or in pipes, where they trap fat or cooking oil tipped down kitchen sinks.

Hidden from view, they grow until a blockage or a sewage spill occurs and a battle-hardened team of sewer technicians has to be dispatched to vanquish the monster.

A council spokesman said the latest rag monster, or “rag ball” to use the council’s less vivid term, was removed from a key Haruru pumping station just before Christmas.

The rag monster had the potential to cause major damage to the wastewater network and took contractors three days to extract.

The Haruru Major Pump Station was a critical asset that took wastewater from Ōpua, Paihia, Waitangi, Haruru and Watea, he said.

It wasn’t even the first rag monster extracted from the Paihia wastewater system in 2022 — another had to be pulled out of the Waitangi Major Pump Station earlier this year.

Rag monsters could grow rapidly, restricting wastewater flows, damaging pipes and pumps, and causing untreated wastewater to spill into the environment.

“Wet wipes flushed down toilets are a major cause of rag balls. Most wet wipes contain plastic, so they don’t break down and instead gather to form balls which soak up food fat and grease,” the spokesman said.

Nappies, tampons, sanitary pads, rags and undies are among the other culprits.

It was a reminder to all households and businesses connected to council wastewater systems that the only material sewage systems were designed to take — other than human waste — was toilet paper.

“Nothing else should ever be flushed,” he warned.

The Haruru rag monster consisted largely of congealed fat and non-flushable items such as wet wipes. Photo / FNDC

Long-standing problems with rag monsters blocking New Zealand’s wastewater systems prompted Consumer NZ to campaign for clear labelling on products such as wet wipes to indicate which could be safely flushed down the loo.

That finally paid off in May this year with the introduction of Australian-NZ ‘flushability’ standards.

The world-first standards, developed by Water NZ, prohibit manufacturers from claiming products are flushable if they aren’t.

The penalties for making misleading claims under the Fair Trading Act include a fine of up to $600,000 for companies and $200,000 for individuals.

Products that do meet the standards carry a logo showing a figure dropping an item into a toilet bowl.

Consumer NZ campaigns adviser Jessica Walker said the organisation had tested “flushable” wipes in the past and found they did not disintegrate.

“They should never be flushed,” she said.

Rag monsters and their evil twins, fatbergs, have also been causing havoc in the Kaipara.

Fatbergs are accumulations of congealed cooking fat and oil that build up in wastewater pipes, potentially causing smelly and environmentally damaging sewage overflows.

In June this year Kaipara District Council operations manager Donnick Mugutso urged residents to dispose of cooking oil, fat, food scraps and other solid kitchen waste in the compost bin or rubbish — not down the sink.

In 2020 Gisborne ratepayers were forced to stump up $100,000 to remove a half-tonne fatberg from the city’s sewer network. The hideous mass was made up of fat, wet wipes and rags.

Another fatberg in April this year caused a sewage overflow near the holiday hotspot of Kaiteriteri in Tasman Bay.

A small portion of the “rag monster” extracted from a Haruru sewage pumping station before it was collected by a sucker truck. Photo / FNDC

Water New Zealand estimates $16 million is spent removing rag monsters and fatbergs from sewers around the country each year.

One of the biggest fatbergs known to man was discovered in the sewers below Whitechapel, London, in October 2017.

It weighed 130 tonnes, stretched more than 250 metres and took nine weeks to remove.

Most of it was converted into biodiesel. The rest was put on display, in a sealed case, at the Museum of London.