TODAY |

Used condoms, tampons being flushed onto Wellington beaches

Cotton bud sticks, tampon wrappers, used condoms, hair pins and razorblade-heads: all items you probably would not want to see again after being used, let alone washed up on our beaches.

Waste from sewage filter at Moa Point. Source: rnz.co.nz

By Harry Lock of rnz.co.nz

But with these items being regularly flushed down the toilet, unfortunately, they are.

Moa Point Treatment Plant, roughly 20 years old, has 70 million litres of sewage pass through every single day.

Those who work there have to deal with more than just the Three P's (poo, pee and toilet paper), but - along with anything else flushed down the toilets - waste from meatworks, restaurants, washing machines, and more.

One of the first steps is to filter out all the objects that should not be going through the pipes. This is done using steel screens 3mm wide.

"They catch the solids that come through, the rubbish that comes through in the wastewater," explained Steve Hutchison, Wellington Water's Chief Wastewater Advisor.

"They lift it up, and they drop it into a conveyor at the back so we can then send it into the landfill."

They have found all manner of objects. Wet wipes are common, but also sanitary items, and even the odd credit card.

There is always a lot of it - about 600 tonnes of the stuff is trucked from Moa Point to the landfill every year. It has become an arduous job, and one they wouldn't have to do if people put the items in the bin.

Hutchison said dealing with what came to the treatment plant was not the main problem, however.

"The bigger problem is back in the network, where you get blockages," he said.

"If you have a displaced joint in a pipe, then a wet wipe can catch on it, then another wet wipe will catch on it, another one, the fat might build up behind it, and before you know it, you've blocked the sewer pipe, and the sewage is coming out and spilling onto the road, maybe onto someone's backyard, maybe onto the stream and harbour."

Teams are called out to unblock these fatbergs a few times every day.

Hutchison believed people were continuing to flush these items because of a persistent lack of awareness in the general public about their impact.

Wellington Water public education campaigns had not worked to much effect, with the scale of rubbish coming through not decreasing.

Meanwhile, many wet wipes continue to claim they are "flushable".

"There's a technical standard produced in Germany which assessed they were flushable, Hutchison said.

"But that was all based on brand new, perfect sewers. What we've got in the rest of the world is some older sewers."

Water New Zealand has been working with other agencies from other nations to try to get the standards for flushable items changed.

Many items not making it to the treatment plant
One charity has spotted another trend with the objects people flush down their toilets.

Tarakena Bay - a small, grey-sanded beach where little blue penguins nest, less than a mile away from Wellington airport - is one of 200 sites being monitored by Sustainable Coastlines' Litter Intelligence Programme.

For three years volunteers have been surveying the beach, and recording what rubbish they find.

"I sometimes feel like I'm a modern day archaeologist doing this work," said Sustainable Coastlines Citizen Science Manager Ben Knight.

"You're often having to piece together what the items are, where they came from, categorise them accurately obviously, and then think about where they might have come from.

"This one here - chapstick tube - could have come through the stormwater system, but also this is the type of item that we typically find when we find the cotton bud sticks. "You can imagine someone throwing it into the loo, flushing it, assuming it's problem solved for them, and then it spilling out of that sewage treatment system and onto the beach."

Knight said they are continually finding tampon wrappers, condoms, hair pins and disposable razorblade heads.

Rural beaches also finding sanitary items
It is not just Wellington's beaches which are exposed to the problem - cotton bud sticks repeatedly pop up elsewhere.

"They are widely distributed within the database, so over 40 sites, about 20 percent of our survey areas, we're finding them.

"I was up at Kai Iwi Beach which is north of Whanganui, a rural beach, just a couple of weeks ago and we found half a dozen of them up there. It just shows you how widely distributed they are."

It not definitely known how these items are getting out of the pipes and onto the beach.

Knight said the theory was that during heavy rainfall events, stormwater got into the sewage system, overwhelming the pumping stations.

That would result in an overflow, with the built-up refuse getting washed out into the stormwater network and onto the beach.

He said such objects damaged the wildlife, the ecosystems, and the general cleanliness of the beaches.

He and Wellington Water agreed there was an immediate - and urgent - solution.

"Ultimately the solution is actually quite simple," Knight said. "In the first instance, don't buy single-use plastic items, sanitary items, personal care items, cotton bud sticks if you can avoid it.

"Where you can't avoid purchasing these items, don't dispose of them in the toilet."

That might stop items washing up on shores, but it would not stop sewage contaminating beaches, and what we see could be just the tip of the iceberg with much much more heading out into the sea, not to be seen again.

"We don't know at the moment what percentage of the total marine litter load comes ashore, but I think it'd be safe to assume it's a small percentage of the total litter load that is making its way out into the marine environment."