‘Contamination is the killer’: Christchurch's old bottles could become new ones under fourth bin proposal

Wednesday, 22 July 2026

Christchurch’s old bottles and jars could soon be recycled into new glass instead of ending up beneath roads if the city adopts a proposed fourth wheelie bin.

A major South Island glass recycler says separate collections would dramatically improve recycling quality and create new markets for used glass.

Public submissions are currently open on the Christchurch City Council’s draft waste management and minimisation plan, and two related policies. One includes a separate glass collection, which could take the form of a fourth wheelie bin.

It would cost between $65 and $75 per year, which one councillor said would be another expense for households already doing it tough.

Council resource recovery manager Dr Alec McNeil said they handled about 15,000 tonnes of glass bottles and jars each year collected in kerbside yellow bins – an estimate the council was using for tendering.

All glass from the sorting facility is currently used as aggregate, with most going into roading. Less than 2% – or 300 tonnes annually – was lost as residual waste in the sorting process, and went to landfill.

Chris Grant is the managing director of 5R Solutions. At its Christchurch-based plant, the glass recycling company already breaks down kerbside collections for eight South Island councils spanning Kaikōura to Dunedin, and takes public transfer station drop-offs from Selwyn, Waimakariri, and Christchurch.

Grant, whose company could benefit commercially if Christchurch adopts a separate glass collection system, hopes to be part of that conversation if the council proceeds with a fourth bin.

“If the Christchurch City Council came on board, the South Island would be doing an amazing job,” he said. “We'd be looking at around 90% of available material at kerbside being collected and repurposed.”

Grant said once glass was used in roads, it was “gone forever”.

But a separate glass bin could significantly boost the recycling value of Christchurch’s glass – turning it into a “gold standard” product and opening it up to new markets, he said.

At his site, bottles divided up by colour were ground into cullet - tiny pieces of crushed glass that can be melted down for reuse at lower temperatures than raw materials.

This was a premium product, able to be sold on and recycled into all kinds of things.

“The best outcome is going back into making new glass bottles from a life-cycle perspective,” he said. “But glass is an inert material by nature … it can go into astroturf, it can go into building products, it can go into coatings, water filtration.”

Glass is the only material Grant knows of that can be fully processed and reused within New Zealand.

One tonne of used glass bottles could be effectively recycled into one tonne of new glass bottles, he said, which also reduced the need to import silica sand to manufacture new glass.

“Plus on the other side, it improves the recyclability of all the other materials in the bin, so you don't get glass shards in your cardboard, your aluminium, your steel cans, plastics.

On the mooted $65 extra cost for ratepayers, Grant said a solution did not necessarily have to “end in that outcome, from a cost perspective”.

He said a separate glass bin would add little extra effort for households. Labels and metal rings could be left on, and other councils they worked with were able to sort by colour at the kerb.

“It’s just purely putting it in a separate bin.”

Members of the public can make a submission on the draft plan and related policies on the city council’s website until Monday, August 3.