The private landfill, at Fairfield, is owned by Transpacific Industries Group NZ, and managed by staff from its wholly-owned subsidiary, Canterbury Waste Services Ltd.
It caters for the estimated 35-40% of Dunedin households - according to last year's council rubbish survey - and hundreds of commercial customers using private collection services, rather than the council's public collection.
Canterbury Waste Services general manager Gareth Jones, of Christchurch, confirmed when contacted yesterday the company's Fairfield landfill was filling up, and could be closed in as little as three years.
That would depend on the volumes of rubbish received in the interim, but even at reduced volumes it was "likely" the landfill would be closed within a decade, he said.
Once closed, there was "no doubt" some rubbish would have to be diverted to the council's Green Island landfill.
"That would increase the volume going into Green Island substantially and reduce its overall life," Mr Jones said.
That would raise fresh questions about what to do with the city's rubbish, as the Green Island landfill was itself expected to close when its existing resource consent expired in 2023.
Councillors are grappling with plans to introduce a new kerbside collecting system, which in part aims to encourage waste minimisation to divert greater volumes of material away from the landfill.
Council infrastructure services committee chairman Cr Andrew Noone yesterday said time was "starting to run out" for the council, which would need to begin planning for the city's future landfill needs within the next "two or three years".
Council staff told the Otago Daily Times yesterday the most recent data on space remaining at the Green Island landfill - from 2008 - showed it was expected to remain open until 2023.
However, Cr Noone said identifying a site for any replacement facility, acquiring land and obtaining resource consents could "could gobble up most of the decade".
"I would suggest time is starting to run out. We have got 13 years and as we know the length of the RMA [Resource Management Act] process could be quite a drawn-out process.
"Time is ticking away and over the next couple of years I would suggest it would be important for the council to put a stake in the ground," he said.
A regional landfill for Otago, costing "literally millions of dollars" and similar to those already developed in Southland and Christchurch, was one option that would be considered.
However, no options had been examined in detail.
"There [are] a number of possibilities council needs to investigate over the next couple of years.
"Whether it's a landfill like the ones that have been developed in neighbouring provinces like Canterbury and Southland, where you have one landfill for the province - that seems to be where things are heading.
"They are the sorts of things that haven't been discussed . . . but they are the sorts of things we need to seriously consider over the next year or two."
Council solid waste manager Ian Featherston said the Green Island site was a "Class B" landfill of the type the Government wanted closed because they did not meet environmental standards introduced with the New Zealand Waste Strategy in 2002.
The council had decided it "wasn't worthwhile" to upgrade its existing Class B landfills, and councillors would instead have to consider alternatives during the next few years, he said.
