As a scheme for achieving the minimisation of household waste, variable (weight / volume based) charging is often suggested. It has been reported that reductions in waste arisings were observed, however it is not clear where (or who) the reduction happened, and what side-effects are taking place in lieu of the observed decrease in waste.

In many cases, private companies as well as the municipality collect business waste together with household waste. It could be that the waste reduction was recorded on the municipal waste statistics due to a shift in service providers. It is also important to know to what type of residents (income levels / housing types etc) this scheme is most effective (or otherwise). Another important aspect is to what extent a "genuine" minimisation has happened, and how much is it due to diversion to recycling. Recycling and minimisation should be grasped as separate concepts.

The efficacy of waste policy is often assessed by analysing the municipal waste statistics. Using the city as a unit for analysis, it is difficult to address the issues mentioned above, as arisings from areas with different socio-economic characteristics are all aggregated into one figure. Waste arisings data including separate collections for recyclables, were made available at the school district level in Fukuoka, Japan. This splits the city (pop 1.4M) into more than 100 districts of a similar size. Using this data, it is possible to cross-analyse waste reduction with area-specific variables, pre- and post-implementation of the variable charging scheme.

At the conference I shall be able to present the results of analyses that are currently on-going (as of Oct '06). Interim results suggest that variable charging encourages the diversion of recyclables from the waste stream, but it does not have a large effect for waste reduction per se.