The council’s consent to operate the landfill at Green Island expires in October this year.
A council spokesman said the potential remaining life of the landfill depended on the amount of waste received each year.
"At present, based on current average annual volumes, the landfill could remain in operation for an additional five to six years," the spokesman said.
In May, last year, council chief executive Sandy Graham told commissioners at the hearing for Green Island’s presumed successor, the proposed Smooth Hill landfill, the council was "actively progressing consents" to extend the life of Green Island on its existing footprint.
Council submissions at that time revealed that in 2019 Stantec investigated expanding the footprint of Green Island, but found it would require infilling waste over the main sewer pipework into the Green Island wastewater treatment plant to a depth of about 25m.
A landfill footprint expansion would make future maintenance of the main sewer pipe extremely difficult and could even result in pipe collapse.
For that and several other reasons they concluded an expansion of Green Island was not a suitable medium-term landfill option.
Council counsel Michael Garbett said during the hearings any consent application to extend Green Island’s use as a short-term landfill option would preferably be lodged early this year.
Conditions imposed on the council when consent for Smooth Hill was granted included the need to prepare a southern black-backed gull management plan and to reduce the existing level of bird strike risk to aviation before the closure of the Green Island landfill where the native birds flocked in large numbers.
The council spokesman last week confirmed an aerial survey of the wider Dunedin area had been conducted to identify the locations of breeding colonies for the southern black-backed gull.
This information would inform the development of a southern black-backed gull management plan for Green Island landfill, he said.
The independent commissioners’ approval of the consent application for a Smooth Hill Landfill has been appealed to the Environment Court.
