No wipes down the pipes

Auckland's Watercare is partnering with Plunket to encourage new parents to keep potential blockages out of the sewage system – in particular, so-called ‘flushable’ wet wipes that are actually nothing of the kind.

The new partnership is aimed at getting a message through to families about the hazard wet wipes cause – not just to the city’s sewage systems, waterways and beaches, but to the risk of homeowners of a big plumbing bill to unblock drains. 

Wet wipes account for by far the biggest percentage of blockages in pipes. Watercare says of the 70 percent of blockages caused by things going down the drain that shouldn’t, wipes make up 40 to 45 percent. Non-dispersible paper comes a distant second at 22 to 26 percent, followed by miscellaneous items and personal products – feminine hygiene products, condoms, cotton buds and dental floss. Fat makes up 2-8 percent of blockages.

Unblocking those pipes costs ratepayers nearly $1 million a year.

Supermarkets still stock a range of wipes that claim to be flushable – something that Auckland Councillor Richard Hills wants them to stop doing. He has personal experience of the problem, after a metre-long fatberg of wet wipes and rags caused a blockage near his North Shore home last year, spilling pollution into a stream on a reserve and eventually into an estuary.

He says Aucklanders are always asking what the council is doing to improve water quality, and are really passionate about water and the environment.

“We are pouring $7 billion into new and upgraded infrastructure in the next 10 years which is great, but in the meantime this is important.

“Don’t pour paint and oil down stormwater drains, but it’s also about not flushing rags, nappies and wet wipes down the toilet. Put them in the bin.

“This is becoming a huge issue. I was astonished to find out wet wipes are about half the problem when it comes to blockages. No amount of infrastructure spending can tackle this wet wipes issue.” 

Hills says it’s only surfaced as a major problem in the last couple of years, since ‘flushable’ (“there’s no such thing”) wipes were stored near the toilet paper in supermarkets. “People are just following the instructions, I guess.”

But he thinks it’s led to the belief all wipes can be disposed of that way, even the ones that contain plastic and can take decades to disintegrate.

He says when they find out about the issue, most people are happy to stop using them.

Hills says it’s a worldwide issue, and councils internationally are looking at action against manufacturers who make claims that don’t stack up. Last year an Australian Federal Court slapped a $700,000 fine for misleading advertising on a wipes manufacturer for claiming its wipes would disintegrate in the sewage system "just like toilet paper".

Consumer New Zealand has previously given the producers of ‘flushable’ wipes a serve, saying the claims are made based on tests run through new PVC piping in a lab – conditions that in no way match those in New Zealand, and don’t account for snagging in sewers. Most New Zealand homes have old earthenware or clay pipes which are highly susceptible to ground movement and tree roots.

The organisation says that in reality the wipes don’t disintegrate, and manufacturers shouldn’t be using the ‘flushable’ claim.

Watercare says no wipes are safe to flush, in spite of what claims might be made on the packet. They simply don’t break down – they snag on other debris and merge together with fatbergs, creating huge, slimy lumps that clog wastewater pipes.

“Most wastewater pipes are only 100 millimetres in diameter and are not designed to carry anything other than wastewater and bio-degradable products, like human waste and toilet paper. But last year, 84 percent of overflows during dry weather were caused by people flushing rubbish down the toilet, pouring cooking fat down the sink, and tree roots that had grown into pipes,” Watercare says.

“Items like rags, sanitary items, wipes, dental floss and nappies don’t break down in the wastewater network. Instead they form large, impenetrable clumps that can block pipes.

“Only the three P’s – poo, pee and paper – should ever be flushed down the toilet.”

At the Māngere waste processing plant, 700 tonnes of wipes are screened out every year – an estimated 53 million wet wipes.

Watercare has a slew of examples of severe wastewater overflows caused by wipe-infested fatbergs, including major spills into streams that led to pollution and dead fish.

Water New Zealand is currently working to establish an international flushability standard agreement, and similar work is being done in Australia.

Plunket’s Northern Region Operations Manager Sam Ferreira says a lot of families are unaware of fatbergs, and the partnership with Watercare is an opportunity to change that.

“We want people to know that if they flush non-biodegradable items - especially wet wipes - they are not only contributing to the growth of fatbergs, they are also running the risk of a wastewater overflow at home and a plumbing bill to fix blocked pipes,” she says.

Help us create a sustainable future for independent local journalism

As New Zealand moves from crisis to recovery mode the need to support local industry has been brought into sharp relief.

As our journalists work to ask the hard questions about our recovery, we also look to you, our readers for support. Reader donations are critical to what we do. If you can help us, please click the button to ensure we can continue to provide quality independent journalism you can trust.

With thanks to our partners