PLANNING FOR SUSTAINABLE MUNICIPAL SOLID WASTE MANAGEMENT
Introduction
As towns and cities around the world expand and populations grow, volumes of waste produced increase and the challenges of solid waste management change. This technical brief presents some important considerations for planning solid waste systems. It begins by outlining solid waste management (SWM) concepts and goes on to describe the process of planning for sustainable municipal SWM. Some aspects, such as planning secondary collection, selecting vehicles and designing landfills are quite complex. Although this brief does not provide in-depth guidance on each of these issues, the final sections do highlight some of the important questions to consider and suggests possible solutions. The brief also provides sources of further information. Responsibility for managing waste usually falls on municipalities, although NGOs, the private sector and the informal sector often play important roles. This technical brief would be particularly useful for municipalities, NGOs or businesses involved in planning and managing solid waste management programmes Solid waste Solid waste is defined as material which no longer has any value to its original owner, and which is discarded. The main constituents of solid waste in urban areas are organic waste (including kitchen waste and garden trimmings), paper, glass, metals and plastics. Ash, dust and street sweepings can also form a significant portion of the waste. Waste is generated by a range of stakeholders including: pedestrians, households, businesses, markets, industries and healthcare facilities. Therefore solid waste can also include toxic waste (e.g. chemicals from industry), biological waste (e.g. dressings from hospitals) and occasionally faeces (e.g. from nappies). These hazardous wastes require specialised treatment and disposal, not discussed in this technical brief. The source of waste often determines its quantities and characteristics. In developing countries waste generated from various sources is often combined at collection and disposal, so due care must always be taken to ensure the health and safety of those involved in waste management.
Photo 1: Door-to-door solid waste collector in Delhi (Jonathan Rouse)
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Planning for sustainable municipal solid waste management
Practical Action
Solid waste management: the basics Solid waste management (SWM) involves the collection, storage, transportation, processing, treatment, recycling and final disposal of waste. Systems need to be simple, affordable, sustainable (financially, environmentally and socially) and should be equitable, providing collection services to poor as well as wealthy households. SWM should aim to improve the environment, provide direct health benefits, support economic productivity, and provide safe, dignified and secure employment. Figure 1 illustrates typical SWM processes. Many developed countries have formal door-to-door collection systems ( in Figure 1). However, in low-income countries waste generators (e.g. householders), domestic helpers or private waste collectors carry waste to transfer points (see photograph 1). This stage is indicated by , and is referred to as ‘primary collection’. A transfer point is an intermediate place at which waste is deposited and stored before being transported to the final disposal site. Local authorities then collect waste from the transfer point and convey it to the fi nal disposal site. This stage is indicated by and is referred to as ‘secondary collection’. Finally, waste is disposed of to a variety of standards according to available resources and knowledge. This stage is called final disposal. Recyclable materials may be extracted from the waste stream from the points of generation, transfer or disposal. In reality there are many variations on Figure 1: for example, sometimes large private sector companies manage everything. Figure 1. Solid waste management process diagram
Source: Rouse and Ali 2002. Stakeholders in SWM are many and varied. Table 1 presents the common roles and responsibilities of various actors. Understanding existing roles is an extremely important first step in planning.
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Planning for sustainable municipal solid waste management
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Table 1: Who does what in solid waste management? Secondary transportat ion Recycling Generation Monitoring Awareness raising Primary collection Sweeping Policy/ Planning Disposal
Householders and other generators Informal sector Private sector NGOs Municipalities Government bodies Common roles Occasional roles
Informal-sector and solid waste management In many developing countries, the informal sector makes a significant contribution to solid waste management. Their work includes: door-to-door waste collection (often contracted informally by householders) and depositing waste in transfer points; purchasing valuable recyclable items from householders and small businesses, thus reducing the overall burden of waste management and recovering resources; and, 'waste picking' - searching for recyclable materials from waste on streets and at disposal grounds.
Planning for improved solid waste management
Many municipalities struggle with achieving acceptable quality and coverage of SWM services due to budget constraints, lack of cooperation of generators, conflicts between different stakeholders, and the difficulty of managing transport fleets and identifying and managing disposal sites. Better solid waste management is important because uncolle cted waste is an eyesore, blocks drains and is a public health risk. Planning sustainable solid waste management can be complex, but a logical approach and carefully considering the various stakeholders and options will increase the chances of developing an efficient, effective and successful system. Planning SWM must include a consideration of each of the stages in Figure 1, and all the actors. Strategic planning Strategic planning (SP) is a logical approach to developing appropriate, achievable action plans for improving the quality, coverage and efficiency of SWM services. It can be summarised by the following three questions: What is happening at present? (Situation analysis) What do you want to happen? (Goals) How can you make this happen? (Strategic plan) SP is a planning tool designed for long-term planning, particularly at town, city or even national level rather than neighbourhoods or projects. It is geared towards developing a vision and long term roadmap with wide ownership following detailed consultations. This technical brief draws on many of the principles of SP, but focuses more on the practical planning issues of improved SWM. See Wilson 2004 for more information.
Situation analysis
Planning begins with a study of the existing situation and systems. Planners should develop a broad understanding of actors, opportunities, constraints, possible partners and so on. Key questions include: What existing information exists on waste streams, quantities and characteristics (see next section)? 3
Planning for sustainable municipal solid waste management
Practical Action
How does SWM work at present? What are its strengths and inefficiencies? What are the existing resources for SWM including personnel, skills, equipment, land etc? What are the financial issues (including budget, cost recovery, forecasting)? What policies, legislation and regulations apply? What level of political ownership/vision exists? Who are the actors? What level of investment and interest is there from the private sector? What are the potential hazards from handling waste? What are the key constraining factors (e.g. lack of co-operation of generators, lack of vehicles, no disposal site etc.)? What are the long-term trends and future needs (e.g. population growth , waste type)? What are the socio-cultural issues and expectations (e.g. attitudes and level of cooperation)?
Much of this information may be secured from secondary sources, though it may be necessary to undertake some primary research. The situation analysis should also involve detailed consultations with a range of stakeholders, as outlined in Table 1 above. The consultation process should also be an opportunity to build co-operation and support and ensure solutions are inclusive and geared towards demand. Such activities must use simple concepts and encourage genuine participation. Waste characterisation The cornerstone of successful planning for a waste management program is reliable baseline information about the quantity and type of waste being generated. This enables informed decisions to be made about equipment, vehicles, storage facilities, specialised handling requirements and personnel. The information can also enable targets to be formulated for reduction and recycling programs, and provide baseline data for assessing whether goals and targets have been achieved . Issues to investigate may include: What waste is produced (constituent elements, density)? Generation rates (i.e. how much waste is produced (volume and mass)) Where is it produced? When is it produced (e.g. seasonal variation)? What are the trends in all of the above (e.g. amount of packaging in waste may be increasing)? What are the potential hazards (e.g. sharps, toxic chemicals)? There are a number of methods for quantifying and characterising waste, but care is required to ensure accurate and representative data. For example, weighing and examining the waste from a sample of households could give an estimate of total household waste produced in a city (multiply by the total number of households), as well as an indication of the types of waste present in domestic waste. However, the sample needs to be carefully selected in order to account for the considerable variation found in some cities, for example between wealthy and poor neighbourhoods. Additionally, it is important to recognize that the characteristics of w aste can change as it progresses towards disposal, processing or recycling. For example, where waste is placed in a transfer point, recyclable materials may be removed and commercial waste added, thus significantly changing its composition, volume, density and mass. Waste characterisation studies may be undertaken at different points in the solid waste management process according to the intended use of the data. For example, household generation rate data could be useful for planning primary collection, but not necessarily so for secondary. Finally, waste generation and composition may vary seasonally. Table 2 contrasts typical waste characteristics in low- and high-income countries. Low-income country 0.5 kg 500 kg per cubic metre Up to 80% 5% High-income country 2 kg 100 kg per cubic metre 30% 40%
Generation per household Density Composition:
Organic Paper
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Planning for sustainable municipal solid waste management
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Metals Plastic Glass
Moisture content
Less than 1% Less than 1% Less than 1% High
10% 2% 10% Low
Before embarking on waste characterisa tion studies, check for existing survey data.
Developing action plans
Sustainable SWM cannot be achieved through isolated approaches, for example by a number of isolated projects, or applying technology or awareness raising alone. Action plans ideally contain a range of activities: some which are easy and simple to undertake in the short -term, as well as activities which contribute to longer-term goals and which require considerable time, effort and investment. Short and long-term activities should complement one another. Goals and indicators Achieving 'perfect' solid waste management is a challenging goal, and achieved by few - if any municipalities around the world. It is often more helpful to develop a ‘roadmap’ consisting of incremental goals and indicators (i.e. ways of measuring performance) to achieve long-term improvements to SWM. Positive change relies not only on hardware investments and systems design, but also mindsets and behaviour. These can take time to change. Practically, this means you may choose to define a series of goals. For example: Short-term goals: to achieve minimum standards, i.e. collect all waste from streets and make minor improvements to disposal facilities (6 months); Medium-term: improve resource recovery and recycling, and improve the quality of the disposal facilities with basic leachate treatment and compaction (2 years); Long-term: achieve 100% source separation of waste, and develop sanitary landfill (5 years). There are a number of ways of developing action plans. One is to draw up a table listing the various functions (e.g. primary collection, recycling, transportation , disposal etc.) and for each function outline the present situation and the goals (including intermediate goals), and then devise a plan for achieving this. At this point you should also identify opportunities, threats, budget requirements and set target dates. Table 2 shows the possible column headings for this process. Table 2: example strategic plan development
Function Disposal Goals 1. Meet minimum standards A ction plan 1. Compact and cover waste 2. Stop all waste burning 3. etc. Opportunities - Vehicles available from other municipal department Threats - Waste pickers - Uncooperative workforce Budget $##.## Target date + 6 months
2. Medium term goal 3. Longterm goal
+1 year +3 years
Sustainable solid waste management options
Generation and primary storage
Why is planning this important? Waste generators are important stakeholders in SWM. The success of SWM systems depend on the crucial support and co-operation of householders, businesses and markets etc. Planning can ensure systems meet their needs.
Understanding and gaining the support of waste generators, including households, shops and businesses, is vital but frequently overlooked. Key planning questions include: What are the present behaviours, perceptions and attitudes? 5
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