Tauranga City Council rubbish audit reveals city's waste habits

An image from Tauranga's most recent waste audit, completed in December and March. Photo / Supplied

Tauranga is still pretty rubbish at recycling and composting.

That's according to the results of the city's latest waste audit, which showed more than two-thirds of things biffed in household wheelie bins and rubbish bags could have been diverted from landfill.

In total, the Tauranga City Council audit, completed in December and March, found only 35.1 per cent of rubbish was actually rubbish - waste that could not be composted or recycled in New Zealand.

Another third (32.9 per cent) was organic kitchen waste - food scraps, essentially.

The rest was evenly split between organic garden waste (16.1 per cent) and things that could have been put in the recycling bin (15.9 per cent) such as paper, glass, plastics (numbers 1 and 2), and steel or aluminium cans.

The results showed a slight improvement from the 2018 audit, where the proportion of real rubbish was 35.1 per cent.

The improvement was largely down to less glass being thrown in general rubbish, from 7.6 per cent in the 2018 audit to 4.2 per cent this year.

This followed the introduction in October 2018 of the council's rates-funded kerbside glass recycling service, which staff report has seen tonnes more glass being recycled.

Trash

The headline results of the wheelie bin audit will be presented in a council meeting today , along with those of an audit of a transfer station.

This found that just under half of the material in a transfer station was "divertable waste" - whether that was recyclable or compostable items, textiles that could go in clothing bins, rubble that could be used for cleanfill or timber that could be composted or reused.

Asked what we could learn from the results, council infrastructure general manager Nic Johansson said more analysis work was being done.

"At a high level ... there isn't too much difference from our previous results, other than the percentage of glass found in a kerbside rubbish bin/bags.

"It makes sense that there hasn't been a change to other waste types as there have been no change to how the services are provided to the community."

The council was not able to provide data yesterday about the volume of waste the city's transfer stations handled last year, and how much of it came from kerbside collections versus other sources.

Marty Hoffart of Tauranga consultancy Waste Watchers, who has done waste audits for councils around New Zealand but hadn't been involved in the Tauranga audit, said the method usually involved dumping rubbish on a table and sorting through it piece by piece - cigarette butts, vegetable peels, hair, onion dip packets and much, much more.

Waste expert Marty Hoffart from Waste Watchers. Photo / File

He said it was a slow and tedious process but produced data that was "very reliable".

What was going into Tauranga's bins was pretty similar to that found in other parts of the country, he said.

Higher rates of food waste in landfill in, for example, Auckland and Hamilton, could reflect Tauranga's long-running efforts to educate residents about composting and worm farms.

"On a national context, we are very similar to most other councils that are lacking kerbside services for organics.

"Most bins and bags look similar to ours - about half of what is going to landfill all over the country is organics.

"We need to capture this material at the kerbside and compost it. Until we can do that, we won't achieve those changes that we all want."

Kerbside organic collection would become even more important as Tauranga became more urbanised, with more multi-storey buildings and smaller yards, meaning people would have less space for composting, he said.

He was glad a separated food scraps bin was part of what the council was considering as part of its planned new rates-funded kerbside collection.

The council was still finalising the details of that collection, including when it would start and what it would cost. The planned 2021 start has been delayed.

Envirohub projects manager Liesel Carnie said attitudes to waste were definitely changing in Tauranga and people were more knowledgable about recycling - plastics, especially.

But there was still a lot of confusion about composting. She said a lot of people did not realise throwing food scraps in the bin was a problem.

This was because, in an oxygen-deprived environment such as a landfill, organic waste produced methane - a potent greenhouse gas.

"They think that because it's organic, it's harmless."

Her general rule was that anything organic could go in the compost and people did not need to be too fussy.

That included meat but also things like pizza boxes or other paper/card that was contaminated with food and could not be recycled.

Compostable packaging was also on the rise but it needed to go in the compost, not the bin, and some could only be commercially composted - a service not available in the Bay of Plenty.

Carnie said the best thing anyone wanting to reduce their waste could do was to address it at the source by buying fewer single-use items or choosing greener alternatives.

Rachel Brodie of Bristak Engineering, Liesel Carnie of Envirohub and Catherine de Monchy of Toi Ohomai were demonstrating the Precious Plastics machine yesterday. Photo / George Novak

Plastic fantastic

Creative arts and engineering have come together in Tauranga to build a machine that can give plastic waste a second life.

The Precious Plastics machine was on display at the Envirohub pop-up in Devonport Rd yesterday.

Toi Ohomai senior academic staff member Catherine de Monchy demonstrated how it could shred plastics such as milk bottle lids, yoghurt pots, bread bags, plastic cups or much more.

These can be melted down into sheets or blocks that could be cut into shapes, or pressed into moulds. She was also hoping it could be turned into a filament for use in 3D printing.

There had been a lot of interest from artists and designers in using the material, but she was keen to hear from anyone - or any business - who might have another idea for how it could be used.