Waste prevention has been accepted as an imperative of environmental policy for nearly three decades in most OECD countries. However, there has been only limited effort devoted to the establishment of evaluation tools, such as indicators, with which countries may assess their performance in waste prevention. Insufficient attention to this issue has likely contributed to a lack of awareness of, and investment in, waste prevention. Indeed, notwithstanding examples of diminished resource use and waste output per unit GDP in many countries, there is confirmed evidence of absolute growth in material requirements, products used, and ultimate waste generation throughout the OECD area and beyond.
In recognition of the multi-faceted and often poorly understood nature of waste prevention, the OECD has published a reference manual on strategic waste prevention ENV/EPOC/PPC(2000)5/FINAL. The reference manual provides guidance to those public authorities that have chosen to design, implement and improve waste prevention policy programmes.
The need for follow-up work specifically directed toward the development of indicators of waste prevention was endorsed by OECD countries in 2000. It was recognised that this work should, inter alia, take into account previous OECD efforts addressing the use of material flow analysis (MFA) as a potential information tool to support waste strategies and a systems orientation (Report on the OECD Waste Material Flows and Resource Efficiency Seminar available from the Secretariat).
The lack of progress in developing waste prevention indicators can partly be explained by the complexity inherent in creating such metrics. At least two reasons support this contention. First, in waste prevention measurement one is trying to evaluate what is not there (waste not generated), which is inherently problematic. Second, unlike recovery, recycling and other waste management activities, waste prevention is defined by changes in a product before it becomes a waste. It is generally more difficult to measure these types of changes than more traditional waste management activities.
To launch this project, the OECD organised in October 2001 an international workshop on waste prevention performance indicators. A comprehensive workshop report is now available. The workshop confirmed a strong and legitimate demand for waste prevention indicators as a complement to other environmental sustainability indicators being used by OECD and others. It was felt that indicators which address recycling and landfill diversion, while necessary, do not provide a sufficient basis for evaluating waste prevention efforts, or for establishing quantifiable and measurable waste prevention targets. Discussions also made clear that waste prevention indicators must be viewed together with associated policy objectives and targets, while keeping in mind broader sustainable development goals. Workshop discussions confirmed that the OECD Pressure-State-Response model provides a useful basis for constructing a taxonomy of waste prevention indicators.
A preliminary taxonomy for waste prevention indicators was developed at the workshop:
a) Pressure indicators, such as " total waste generation" or "reduction of waste hazard" indicate direct pressures. Indirect pressures can be indicated by Material Flow Accounts of society, such as "Total Material Requirement" or "Direct Material Input". Relative pressures can be revealed through plotting waste generation against appropriate drivers, such as GDP, Private Final Consumption or population;
b) State indicators, such as reduced impact of waste on air, water and soil quality; and
c) Response indicators, such as introduced regulations and plans or expenditures for waste prevention.
The Over-arching workshop recommendations were the following: