Dunedin city councillors will decide next week which of two new landfill charging regimes the public should be consulted about.
The options are a weighbridge or a more refined version of the present charging structure, based on item or vehicle size.
Under the first option, users would be charged by the weight of the waste they want to dump.
Under the second, they would continue to be charged by bag or vehicle size, with the addition of specified fees for wool sacks, wheelie bins and part-loads.
The weighbridge option would be more consistent and fair, but would mean some users would pay more, and some less, council water and waste manager Laura McElhone said in a report councillors will discuss on Tuesday.
For example, an assessment of 21 cars with rubbish recently weighed as part of an audit at the Green Island landfill, showed 14 would have paid less and seven would have paid more over a weighbridge, than the present car charge of $18.
The car with the smallest load in the test (40kg) would have been charged the proposed minimum fee of $5.20 and the car with the heaviest load (260kg) would have been charged $33.20.
In both options, fees would be based on the fact it cost $130 per tonne for the council to dispose of the waste deposited at the landfill.
A weighbridge was not expected to increase the overall revenue and would still require some booth operator discretion to determine whether loads consisted of general waste, 100% vegetation or mixed vegetation. Vegetation loads would be charged at a lower rate.
The $150,000 cost of the weighbridge could be covered by deferring some landscaping work at the landfill for a year.
Alternatively, by adding new fees for wool sacks, wheelie bins and partial loads, further training booth operators to be consistent in their application of the revised fee structure, and educating the public about minimising their waste, the fairness of the present fee structure could be improved, Dr McElhone said.
However, if the revenue level was to be maintained, the fee for a ''full load'' would need to be increased to cover a lower ''part load'' fee, meaning people who deposited ''average'' loads would pay more.
She said there was a philosophical argument to be had with regards to whether weight or volume was the more appropriate approach to charging.
That was based around which was more representative of the environmental impact of waste and which was more representative of the proportion of operating costs associated with the load.
Staff considered weight to be the better approach, because Government reporting and waste levies were based on tonnes. Volume was difficult because things were compressed in the landfill and there was no reliable way to accurately measure volume. Weight-based charging allowed for a differential to encourage or discourage certain materials, she said.
Staff recommended councillors approve the weighbridge option and include it in the draft 2014-15 budget.
The public has the opportunity to make submissions on anything in the budget between March 15 and April 15.