Published September 13, 2006
A number of Canadian municipalities have identified that the diversion of residential organic waste from the municipal waste stream will provide significant benefits for the sustainability of the community, extend the life of their landfill facilities and reduce the potential for leachate and the production of methane. Some municipalities have tackled the issue by collecting pre-sorted organic waste from residential properties as part of the municipal waste collection services. In this case study, we look at the use of bags, bins and carts for the collection of waste. We also look at the effect of having an integrated provincial-wide waste management strategy, which includes the banning of organic waste from landfills entirely (such as in Nova Scotia) and explore alternatives to central composting facilities. This case study focuses on two examples of organic waste collection – one province-wide in Nova Scotia and one city-wide in Whitehorse. These were chosen to provide two examples contrasting provincial with town scale systems, and where the collection stands alone or is integrated into a comprehensive waste management strategy.
Figure 1. Green Bins ready for collection in Toronto
Sustainable Development Characteristics
In Canada, 50% of all solid waste is organic, and, therefore, potentially compostable1. Organic waste that enters the municipal solid waste stream often ends up in landfill. In addition to filing up landfills, as the waste biodegrades it produces leachate, which could infiltrate the ground waste and potentially contaminate drinking water supplies, and methane, which costs money to control and has the potential to create local pollution problems. Most municipalities have policies to reduce the amount of organic waste in the solid waste stream, most frequently these programmes encourage residents to set up composting in their backyards and in many cases municipalities, for example Kingston, ON, Vancouver, BC, Innisfail, AB, and many others, provide the resources for householders to compost their yard waste – either by taking it to compost sites, or by organising collections.
There are disadvantages to these methods: some compostable material can’t be composted in standard backyard composting equipment due to odour, health and rodent concerns (materials such as meat, fish and bone). Also, apartment dwellers and others who do not have the resources or storage facilities for composting are unable to backyard compost. In order to increase the amount of organic waste that is diverted from landfill a number of municipalities have instigated curbside collection of organic waste alongside collections of garbage and recyclable material. This reduces the amount of waste entering landfill. In 2002, across Ontario where organic waste is disposed of largely into landfills or by backyard/on-site composting, 0.14% of generated waste was composted2. By contrast, in Nova Scotia where the provincial move to remove organic waste from landfills has resulted in 80 to 90% of residents disposing of their organic waste in green bins in one of eighteen composting plants around the province – up to 50% of household waste is made up of compostable material, which represents a significant waste diversion3. Reducing its organic component, makes a landfill cheaper to operate and less likely to pollute the surrounding land, air, and water. The production of compost allows the potential for cost recovery through the sale of the material, and reduces the dependence on commercial compost by gardeners and landscapers, which may not come from sustainable sources and/or inputs.
Lundie and Peters (2005)4 have found that, of the various disposal methods available for food waste management, the backyard system is the simplest, whereas the centralised system is the most complex. They also found that centralised composting is more energy intensive than most other options, such as garborators, and co-disposal, as a result of the transportation requirement of the collection system, although the example system they were studying operated a parallel two weekly collection process. In contrast, the typical approach in Canada is to replace a regular collection with an organics collection – thereby reducing the transport impacts. It also depends on the method of composting used centrally – anaerobic systems are much less energy intensive than aerobic systems5.
Critical Success Factors
Initially, there was significant investment in research by the provincial government, in order for the policy and legislation to be workable, and to win the confidence of the municipalities and residents of Nova Scotia. This process was started as a result of citizen pressure, supported and undertaken by consultants who were influential in the process, and led by the Solid Waste Resource Management group in the provincial department of Environment and Labour.
Operating at a provincial scale was vital for economies of scale, allowing for efficient collection of waste in a coordinated manner. The scale also meant that a critical mass of knowledge was achieved leading to knowledge diffusion, increasing the opportunities in the province for employment in waste management and waste consultancy.
Including the organic waste strategy as part of a comprehensive waste strategy.
Using both legislative sticks (e.g. potential for fines, and actual examples of whole loads from a municipality being rejected at the landfill) and resource carrots (e.g. money gained from recyclables such as bottle deposits is partly returned to the municipalities based on the amount of waste diverted from landfill) to encourage municipalities to improve their performance.
The biggest barrier to the project from the moment of conception was the lack of council support. The slow progression through two small pilots was essential in achieving the support of both the council and community, and the success of the project.
The availability of territorial and provincial funding allowed an initial solid waste management review, which led to the project.
Using social marketing through volunteers in neighbourhoods to win community support.
Green bin collection works best in areas with denser populations and economies of scale that enable significant volume diversion from landfills. In remoter and/or rural areas, investment in better equipment for backyard composting may be more appropriate, supported by education and information dissemination.
Education and communication is always vital. Use of social marketing techniques in Whitehorse and the use of slow roll out/piloting in many places helps to ensure people and neighbourhoods ‘see’ the value and ease of use of green bin collection.
Community Contact Information
Solid Waste-Resource Analyst Nova Scotia
Department of the Environment and Labour
PO Box 697
City of Whitehorse
2121 Second Avenue
Whitehorse achieved success using social marketing to recruit pilot volunteers.
Green carts allow for easy and efficient collection, and provide a focus around which education and publicity can be developed.
Residents like the collection system as it is easy to manage and is part of an established system, requiring little extra effort.
Rejection of waste at collection or landfill, if organic content is too high, ensures monitoring takes place curbside and increases participation in waste separation.
Participation rates are high especially if unsorted waste is rejected.
What Didn’t Work?
Biodegradable bags are not as successful as green carts/bins in providing clean, easy and efficient waste management, or as good quality compost.
In order for cost savings to be achieved, organic waste collection needs to be part of a comprehensive waste management strategy.
The sustainable benefits of central composting are not as great in rural areas or where neighbourhood composting is possible.
Financial Costs and Funding Sources
A publicly available and comprehensive cost benefit analysis for Nova Scotia's solid waste management program, including environment and social costs and benefits, was undertaken by Genuine Progress Index Atlantic6 (GPI).
Funding for collecting compostable materials has been met largely by the various municipal budgets, although in general, the solid waste management funding is returned to the municipalities through the receipt of bottle deposits (50 % of deposits from bottles goes back to the consumer, 50 % goes to municipalities, research and education projects supporting the waste management program).
The program does, of course, cost municipalities more in collection costs, plus most municipalities provide their householders with green carts or bins for the storage of organic waste between collections (normally every other week). In most municipalities across the province this was added to the existing collection of garbage and recyclables either weekly or bi-weekly.
The closest thing to a standard economic comparison for the organic component of the solid waste management program is a study done by the Town of Bedford (part of the Regional Municipality of Halifax) and updated in the GPI accounts. While the figures were produced with the aim of supporting backyard composting over curbside collection as the regional municipality was initially resistant to the idea of curbside collection, they nevertheless give a breakdown of costs.
Table 1. Costs and avoided costs of backyard composting in Halifax, based on the Bedford backyard composting study ($C2000)7
|Year 1||Year 2|
|Bin subsidization (37,235 bins @ $37)||$1,377,695|
|Public education and promotion||$112,042||$112,042|
|Curbside collection (5,344t @ $75)||$400,800||$400,800|
|Disposal (5,344t @ $59/tonne net )||$315,296||$315,296|
|Program costs less avoided costs||$773,641||($604,054)|
The figures were devised for a specific agenda, and also do not include the details, such as the cost of green carts, or an analysis of costs to the town if a load is rejected at the landfill as the content of organic waste is too high, but it doesgive an indication of the some of the costs. Also, the figures do not show the opportunity costs, or the long-term costs of not reducing solid waste accumulation.
Grants were available to the municipal government for the initial strategy and the construction of the compost facility from the territorial government. The territory also paid for the introduction of compost collection at schools within the municipality. The grants allowed the municipality to carry out an initial waste management strategy.
Residents pay for the bio-degradable bags in which the compost is collected. Residents are also charged $7.25 per month for waste collection and disposal (garbage and organics). This pays totally for the collection ($5.25 per month per household) and for 50% of the operating costs of the landfill. Remaining costs are covered through general tax revenues.
The municipality pays for tipping and collection costs through the residential charge and general taxation. These costs have increased since the program started. In 20058, the landfill operators General Waste Management charged a flat fee of $220,000, and in 20059, the compost facility (managed by a non-profit organisation Raven Recycling) charged per tonne, which cost a total of $50,000. As more waste is diverted from the landfill, the program costs more. Revenue earned by Raven Recycling from the sale of compost (at $7 per 55lb bag) offsets its costs of operation.
A cost benefit study has not been done, however, the landfill life has been extended – although its life expectancy was over 100 years anyway, and currently only 1,000 t out of 15,000 t entering the facility is compostable material. Some jobs have been created by Raven Recycling. Sustainable compost is also available for purchase by residents, and the municipal landscaping department gets 25% of the compost for free.
The municipal administration is lobbying for the introduction of carts as there are problems with the bags. The cost to supply householders with carts will be $1M, but collection costs will be reduced. Council is, however, unwilling to support this due to the initial capital outlay involved. The Canada Winter Games, held in Whitehorse in 2007, will purchase a supply ($40,000 worth) of green and other garbage carts for its aim of holding a zero waste games. These carts will then be given to the municipality to run a cart collection system city pilot with over 450 households. It is hoped this will increase participation and convince council to purchase the carts city-wide.
There have been no cost savings. In fact costs have increased. Although free compost is used by the landscaping department, they would probably do less landscaping if it was not available rather than spend more money on other sources of compost.
Analysis leads to these key observations:
There is some debate as to whether a centralised system of composting is more sustainable than neighbourhood or backyard composting. Figures for at which point density increases the effectiveness of a centralised system over a neighbourhood system are not available, but would be worth exploring. A centralised system makes composting easier for the householder, resulting in more composted material, providing greater environmental benefits. Also, economies of scale make waste management more financially viable. In addition, central large scale projects increase the viability of creating a market for the compost – generating income for the municipalities to help cover the costs. However, the centralised system has greatly increased waste transportation16 leading to increased traffic and air pollution. An intermediate solution might be a neighbourhood-wide system that could also provide a local area with their composting needs.
The degree to which curbside collection is the most successful way of achieving sustainable benefits needs to be researched. Annapolis Royal – a rural area of Nova Scotia - has not implemented organics collection, but has provided free backyard composters and composting cones, which enable the composting of materials not normally suitable for backyard systems (e.g. meat, fish, and bones). Waste diversion in Annapolis Royal is more successful than other backyard only composting programs17. GPI recommends that centralized collection may be the best option in urban areas, but not necessarily in rural ones. What are probably needed are diverse, distributed systems in lower density areas and a centralised system in higher density areas. There is probably a continuum from individual to centralised systems as population density increases.
There is anecdotal evidence in Nova Scotia and Whitehorse, which suggests that centralised organics collection is more likely to engage local people than a backyard/neighbourhood approach. Greater engagement with residents is likely to increase the amount of residents taking part in organics waste diversion. Even though the sustainable benefits per person may be less with a centralised system when compared with neighbourhood or backyard systems, the total waste diverted by the community may be sufficiently great as to outweigh the disadvantages. Across Canada, municipalities with organic waste collection generally divert more waste than those that don’t. However, waste collection is usually part of a wider comprehensive waste minimisation strategy involving more recycling and similar strategies. It is difficult to assess the specific contribution of organics collection.
The lack of cost benefits in Whitehorse compared to Nova Scotia may be linked to a lack of critical mass. Size of operation perhaps prevents significant cost savings, and inhibits the development of significant knowledge capital and improvements to the local economy. Because of its remote location, Whitehorse is unable to develop more comprehensive sustainable waste strategies as recyclables are not collected by the municipality – the cost of trucking them to a processing facility means that centralised privately owned and operated depots are the only recycling facilities available in the municipality. As with the issues with collection in rural areas, the question remains whether there is a minimum population size and density for sustainable composting collection processes as opposed to improved backyard composting?
The distribution of green bin programs across the country suggests that there are low barriers to implementation. Despite potential issues with extreme cold, there are examples in most climate zones, and examples is most community sizes – although, as previously stated, the gren bin programs programs may be more appropriate in larger communities with denser populations.
Detailed Background Case Description
Dealing with organic waste
Organic material entering the landfill produces management problems with the production of leachate and methane. Most municipalities within Canada have taken some measures to reduce the amount of organic waste that enters the landfill. These measures include:
The encouragement and subsidisation of backyard composting
Usually the least effort to the municipality, backyard composting relies on active participation of householders and, even with a high level of education and promotion, is likely to achieve lower waste diversion rates than other forms of composting programs, especially in high urban settings. In addition, most backyard equipment is unable to handle the most extreme forms of organic waste such as meat and feces. Also, large volumes of waste, for example from restaurants or multi-unit dwellings, cannot normally be accommodated by this method. Examples of municipalities which provide subsidised backyard composters are Chilliwack, BC, Vaughan, ON, and Hamilton, ON.
Provision of “bring your own” neighbourhood composting facilities
This also relies on the active participation of residents to bring compostable material to local composting facilities, but reduces the problems of more noxious and/or voluminous organic waste and generates more commercially viable compost. The technology available for large composting facilities allows the compost to be produced at higher temperatures, killing pathogens and speeding up the composting process from that achievable through backyard composting. Facilities such as this are being considered, or implemented in North Cowichan, BC, and Winnipeg, MB.
Some municipalities (e.g. Edmonton, AB) sort their waste after collection and delivery to a processing plant. Halifax, NS, sorts garbage post-collection in addition to having a program of separation prior to collection. This increases the amount of waste diverted, but reduces the quality of the compost. All potentially compostable material (including paper, cardboard, biodegradable plastics, etc) is then shredded and composted centrally. Compost produced by this approach is not as good quality as that produced by pre-sorting waste, but is nevertheless useable as a supplement for other compost, and as subsurface layer in the creation of new lawns. The process also reduces the total waste entering landfill even further. In Halifax, the waste diversion rate is 56%10, compared with a provincial average of 46%11, and although what proportion of this is due exclusively to the organics component is unclear, the additional post-sorting does improve diversion.
This is most likely to engage residents, but is the most costly option for municipalities as a result of the higher collection costs and provision of suitable carts or bins for temporary household organics storage. It is also the simplest program to manage, fitting into established methods of garbage and recyclable material collection.
In Nova Scotia, municipalities have adopted different approaches to achieve similar goals, and most municipalities have adopted a curbside collection using green carts. More municipalities are implementing such a scheme as it has been shown to be a successful response to the banning of organic material from provincial landfills. Exceptions to this trend are largely in rural areas where the increased costs of collection outweigh the costs of increased promotion and education for backyard composting. As a result (except in the case of Annapolis Royal), those municipalities not operating curbside collections have not been as successful in the diversion of organics from the solid waste stream, due to the limitations of many backyard technologies in the management of such items as meat.
Whitehorse initially adopted the use of biodegradable bags, which has not been entirely successful as supply has been intermittent, leading to occasional shortages. The bags sometimes degrade in storage and create a problem with the management of organic waste for the householder. The preferred solution, in the opinion of the municipal officers, is the adoption of green carts as these are easier for both the householder and the garbage collection service. The advantage of bins or carts is that the collection process can be mechanized, making it quicker and more efficient.
Green bins are the most common receptacle in use. They are also referred to green carts, especially in larger models. This is the approach taken in towns and cities such as Toronto, Markham, Niagara, and Durham in Ontario, Olds in Alberta, Fundy in New Brunswick and Ladysmith in British Columbia.
In the 1970s, waste management was highly unsustainable and hazardous, with practices such as open burning and illegal dumping in common practice. During the 1980s, because of media attention on waste issues and a landfill crisis (e.g. Halifax took 10 years to find a suitable location for landfill) public opinion began to take exception to this approach leading to a provinc- wide public waste management consultation. The solid waste strategy and subsequent legislation included the banning of organic material from the landfill stream, as well as a comprehensive effort on waste diversion and reduction involving banning materials that could be diverted such as organics and recyclable material, deposits on beverage containers and other management approaches such as new landfill standards (Dec 31, 2005). Many landfills were closed at this time – reducing the total number in the province to 7 (although there are still 25 privately run construction waste landfills in the province).
The solid waste strategy was significantly influenced by the Municipality of Lunenburg, which, in 1991, was the first municipality in North America to instigate a solid waste management review process, and implementing curbside collection in 1993-4. There are strong links between this community and Germany – and people involved in the review had knowledge of the German curbside collection of organic (and other) waste (see the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety for more details); the municipality decided to implement this process. The compost that is created is sold back to residents by the municipalities, which creates another income stream to support the operation of the system.
The scale and comprehensive nature of the Nova Scotia solid waste management policy resulted in a critical mass of knowledge and expertise in waste management, which resulted in significant new economic activity, creating up to 1,200 new jobs. It also resulted in increased interest in composting in the private sector. The pulp and paper industry in the province is now composting wood waste, and McCain's is composting all of its potato peelings in a large scale anaerobic composter12.
The ability to experiment with ideas and techniques designed to increase waste diversion and reduction has led to Nova Scotia becoming a significant centre of consulting and waste engineering companies. Examples of companies that have transferred knowledge from Nova Scotia to national and international markets include Dillon Consulting, the MacDonnell Group, and the Miller Composting Corporation.
In the early 1990s, territorial funding was available to carry out a solid waste management audit (1993-1994). During this period, municipal officials attended a waste management conference where an organic waste management program from PEI was presented involving curbside organic waste collection. The lesson was taken back to Whitehorse. Whitehorse officials decided that they could introduce curbside collection in Whitehorse. Recyclables collection is not cost effective for the municipality as it costs too much to transport material to processing depots. Consequently, recycling in the community is carried out by the private and non-profit sector, and is based on voluntary deposits at collection depots by residents.
There was initial involvement in the development of the waste management strategy of the now disbanded non-profit called LOTS. Territorial funding supported the waste management strategy development. Federal funding was used to build the compost facility at the landfill. A non-profit organisation runs the composting facility at the landfill. Attempts have been made to create partnerships with private companies to increase the management of waste, but this has currently not been successful. Indeed, private companies have been reluctant to collect organic waste from commercial enterprises, a collection service which the municipality does not provide.
The key to winning council support was the instigation of pilot studies. First, in 2000, interested residents formed a process pilot study. These interested residents were removed from the regular collection stream (Monday to Wednesday) and moved to a Friday collection. Following the success of the pilot, in 2001, an entire neighbourhood was selected as a second pilot study, which included both a willing, and unwilling, resident pool. Despite initial resistance from some residents, the second pilot study was also successful. In 2002, the program then went city-wide. The initial group of residents was selected by using volunteers to undertake a community-based social marketing process. This process involved using residents that had been engaged with the municipality on environmental issues, and were interested in supporting the initiative. These people then spoke with their neighbours and friends in an effort to recruit them for the volunteer pilot study.
The basic operation of the organic waste management process works like this: every other week, alternating with regular garbage pick up, organic waste is collected and transported to a compost facility at the Whitehorse landfill. The waste is collected in bio-degradable bags, which are purchased by residents. There is also a limited program of compostable waste collection at schools in the municipality. A non-profit organisation managing the compost facility sells the compost that is created and uses this to offset the cost of managing the facility.
Roadblocks to attractng commercial enterprises have not been overcome. The municipality has started to collect organics from schools as private enterprises would not provide the service as they already do for regular garbage. There was an attempt to instigate an organics collection at the two MacDonald’s in the city, but although 90% of their waste is compostable and composting would save them a lot of money, the franchise holder did not take up the scheme because one of the restaurants formed part of a Wal Mart and Wal Mart handled the waste for them at that store, meaning cleaning protocols would be different in each of the two premises. This was considered unacceptable.
Other examples of green bin collections
In 2002, curbside collection in the Greater Toronto area started in Etobicoke, which acted as phase one of the roll-out of collection services across the metropolitan area. The program was instigated as a result of the closure of the Keele Valley Landfill site in 2002. This meant that Toronto’s waste was then exported to Michigan. At the time, this led to a 400% increase in the cost of garbage disposal13. With 41% of Toronto’s waste being potentially compostable, organics collection was identified as a key component of a waste reduction process14.
Over the next 3 years, the Green Bin Program was rolled out across the metropolitan area. Scarborough began in June 2003 and Toronto, East York and York joined in September 2004. On October 25, 2005, 124,000 single family homes in the North York community came on board, bringing the total to 510,000 single family households. The program does not currently cater for multi-family units such as apartment blocks, although pilots are underway to test the feasibility of collecting organics in such complexes.
Composted material is collected every week, with regular garbage being collected every other week. Compost is placed in green bins that are then left at the curb for collection.
Fundy in New Brunswick adopts a voluntary approach. Curbside residential collection commenced in 2001, using green bins for mechanisation. The key difference in Fundy is that participation in the scheme is voluntary – residents can opt into the program and receive a green bin at their discretion. The program is gaining increased support in the community, with percentage increases in composting and participation in the programme.
Like Nova Scotia, Prince Edward Island has adopted a province-wide approach although the scale is perhaps somewhat smaller. Also, like Nova Scotia the approach is part of a comprehensive waste management strategy.
There are many other green bin examples around the country – mostly operating a model of central composting providing a sellable resource and a mechanised collection using green carts of various sizes. Other potentially sustainable uses for organic waste is to use organic waste to generate fuel for power generation. There is a wide range of processing technologies available on the market and the costs associated with the process are comparable with composting, as well as providing benefits in other areas, such as reducing the reliance on fossil fuels for energy production. This alternative, however, further increases the centralisation of organic waste processing and does not provide communities with a source of sustainable compost. The various strands of sustainable development represented by these various approaches would be difficult to compare and analyse.
What is the critical threshold that moves the most efficient composting program from the backyard to centralised systems?
Which is more sustainable – composting or using organic waste in biofuels/cogeneration projects?
What is the most efficient collection schedule that combines curbside collections of organic waste, recyclables and garbage while keeping vehicle emission to a minimum?
Resources and References
- Composting Council of Canada: http://www.compost.org/
- Ontario Ministry of the Environment. 2004. Ontario’s 60% Waste Diversion Goal – A Discussion Paper, http://www.ene.gov.on.ca/programs/4651e.htm
- Friesen, B. 2002. Which Methods Work Best? Biocycle, Vol 43 (6), p 29-37
- Lundie, S. and Peters, G.M. 2005. Life cycle assessment of food waste management options, Journal of Cleaner Production, Vol 13 (3), pp275-286
- Björklund A, Dalemo, M. and Sonesson U. 1999. Evaluating a municipal waste management plan using OWARE. Journal of Cleaner Production Vol. 7 pp271–80
- The Nova Scotia GPI Solid Waste-Resource Accounts. 2004. GPI Atlantic, http://www.gpiatlantic.org/
- Ibid. Number of bins based on 50% of qualifying households. The cost to residents was $25, and the municipality payed the rest of the cost, a total of $37. Curbside collection costs based on 11.96 kg organic waste per household per month.
- Whitehorse Star, Jan 24th 2005
- Halifax Regional Municipality. 2005. Solid Waste Resource Advisory Committee Minutes September 8, 2005
- GPI, 2004
- Bob Kenny, pers. comm.
- City of Toronto. 2002. Going Green in Etobicoke Issue 1, City of Toronto
- Waste Diversion Task Force. 2001. Task Force 2010, City of Toronto
- Arlt, A. 2003. Processing of biowaste to biofuels – comparison of process chains for sewage sludge, organic and woody waste using a systems analysis approach, Karlsruhe: Forschungszentrum Karlsruhe