The high costs of alternative rubbish disposal methods mean Northland's trash will continue to be dumped in landfills for years to come.
The Whangarei District Council has voted to continue to develop a regional landfill at Puwera, near Portland, after a study found that alternative waste technology could cost more than
four times as much as rubbish dumps.
Northland's three district councils - Whangarei, Far North and Kaipara - commissioned a report on alternative residual waste disposal technology options as part of investigations into the feasibility of a regional landfill.
One of the aims of the report was to find if there could be waste technologies that would offer a viable alternative to landfills.
The report, presented to the Whangarei District Council on Wednesday, found that alternative disposal methods could cost up to $260 a tonne, compared with landfill costs of between $45 and $55 a tonne.
The report looked at four alternatives:
• mechanical separation methods
• biological processes
• thermal (incineration) technologies
• and mechanical biological treatment.
It concluded that the best results for Northland's councils would be achieved by providing an integrated portfolio of technologies, with landfill disposal being an integral component.
The council voted to continue to develop the planned landfill at Puwera, where it would cost $10 million to build a new dump on Whangarei District Council-owned land.
The council is the only authority north of Auckland with full consents to operate a new landfill site. Its planned dump at Puwera would have an expected life of 55 years.
The council also voted to continue to explore alternative waste disposal methods, but acknowledged that landfills were the way to go - for now.
The report said some alternative technologies such as thermal and biological were still in their infancy.
The net cost of mechanical biological treatment was about $120 a tonne, thermal incineration cost between $180 and $260 a tonne, mechanical separation $80 to $120 a tonne and biological up to $150 a tonne.
Once the landfill is open at Puwera it will take almost all of Northland's waste that is not recycled.
