1 Introduction

 

The objective of this report is to help territorial and regional authorities to establish kerbside collections for household organic waste. Household organic waste can include kitchen waste and green waste.

Separating organic waste at the household level provides many benefits, including:

  • recovery of a resource (organic material) from the waste stream
  • provision of a steady supply of organics to composting facilities
  • production of compost - and potentially energy from biogas
  • diversion of organic material from landfill
  • reduction of leachate and landfill gas emissions associated with having less organic material in landfills
  • provision of an alternative for those who are unable to compost at home (eg, those who live in apartment blocks)
  • achieving the organic waste targets set out in the New Zealand Waste Strategy (Ministry for the Environment, 2002).

The Auckland Organic Waste Working Group (AOWWG) [The AOWWG consists of representatives from the Auckland, North Shore, Manukau and Waitakere City Councils.] commissioned this report to form part of a suite of reports [The other reports are: URS New Zealand Limited, 2004a, 2004b; WasteNot Consulting, 2004.] that cover aspects of household organics kerbside collection, from separation at source through to composting technologies and market issues. The reports cover food-waste composting technologies, food-waste market issues, and a comparison of the "disintegrability" of plastic bags in VCU® (vertical composting unit) processing.

1.1 Scope and objectives

The scope of this document is to assess organic waste kerbside collection methods - both systems already implemented and those undertaken on a trial basis - and to identify matters for territorial authorities to consider before implementing a collection of this nature. The main objectives of this report are to:

  • discuss key issues and gaps that need to be taken into consideration for collection systems in New Zealand
  • summarise kerbside food-waste collections in New Zealand, in terms of the results and issues encountered
  • summarise any overseas work that may be relevant to New Zealand
  • present a methodology for assessing and comparing various kerbside organic waste-collection systems.

Note: the following are not within the scope of this paper:

  • a cost-benefit analysis of various kerbside organic waste collection systems
  • assessment and/or details of food-waste composting technologies
  • information on developing markets for food-waste compost.

1.2 Structure

The next section discusses the factors to consider when selecting kerbside organic waste collection systems. It covers the merits and drawbacks of various kerbside collection systems based on the case studies that are reported in depth in the appendices. In particular, section 2 includes a discussion of types of organic waste, options for kerbside organic waste collection systems, frequency of collection, monitoring and trialling of collections, householder education, and market issues. Section 3 presents a methodology for assessing and comparing various kerbside organic waste-collection systems, and section 4 provides the conclusions of this report.