Waste is the symbol of inefficiency of any modern society and a representation of misallocated resources. Waste is considered as an ‘end-of-life’ product, as well as a social and environmental problem. Disposal as an ‘end-of-pipe’ solution has been widely considered to solve the waste problems since the early nineteenth century. After introducing the concept of sustainable development, resource recovery based sustainable waste management has been introduced as one of the key indicators of good governance. After three decades of application of sustainable waste management, the waste problem has never been solved, instead it has been difficult to manage.
Consumption-driven society produces an enormous amount of waste every day. A recent study done by the United Nations shows that, currently, the world’s cities generate about 1.3 billion tonnes of solid waste per year and the volume is expected to increase to 2.2 billion tonnes by 2025. Waste generation rates will more than double over the next twenty years in lower income countries such as Bangladesh. Unexpectedly, waste management systems have not received as much attention in the city planning process as other sectors like water or energy.
In recent years, zero waste concepts have emerged to the local authority as one of the promising waste management philosophies. According to the Zero Waste International Alliance ‘zero waste’ means designing and managing products and processes systematically to avoid and eliminate waste, and to recover all resources from the waste stream. Hence, zero waste is a goal that is ethical, economical, efficient and visionary, to guide people in changing their lifestyles and practices to emulate sustainable natural cycles, where all discarded materials are designed to become resources for others to use.
In traditional waste management systems, waste is considered as an ‘end-of-life’ product which is produced at the last-phase of resource consumption. Zero waste challenges this traditional definition of waste by putting forward a new concept, recognising that waste is a transformation of resources which happens at the intermediate-phase of the resource consumption process. The resources which transform into waste as a result of our consumption activities should thus be redirected into the production process through the holistic zero waste management system.
Zero waste is a combination of integrated design and management philosophy. Under the zero waste philosophy, both product design and waste management principles are considered simultaneously to eliminate potential threats to the environment caused by human consumption and behaviour. The zero waste product is the cradle-to-cradle designed product that does not produce any waste during its life cycle. The zero waste product eliminates the ‘waste phase’ from the traditional product lifecycle because after the end-of-life phase, the zero waste product could either be reused, repaired or remanufactured to produce a secondary product. If not, the zero waste management ensures that the discarded waste would be either recycled, recovered or easily be nourished through natural process, without polluting our natural environment.
More than 50% of the world’s population live in urban areas and some estimates have suggested that 80% of the human population will dwell in urban areas by 2030. Cities cover only around 2% of the world’s surface, consume over 75% of the world’s natural resources and generate 70% of all the waste produced globally. Today, many developed cities such as Adelaide (Australia) and San Francisco (USA) are aiming to transform their current waste management practice into a more efficient and sustainable zero waste practice.
The concept of the “zero waste city” includes a 100 per cent recycling rate and recovery of all resources from waste materials. However, transforming current over-consuming cities to zero waste cities is a challenging task. As a lead researcher at the Zero Waste SA Research Centre, the writer identified both short term and long term drivers of transforming current cities into zero waste cities. Awareness and education, behaviour change and systems thinking are long-term strategies, whereas cradle-to-cradle based innovative industrial design, legislation, 100% recycling and diversion are the short-term strategies to implement in a city. One of the important aspects of the zero waste city is the conversion of the linear city metabolism to a circular ‘closed-loop’ city metabolism.
How can Dhaka be adapted to and benefited from the holistic zero waste concept in its local context? The case of Dhaka is not favourable to implement zero waste concept due to its socio-economic, cultural, institutional and technological differences.
Dhaka is one of the most densely populated cities in the world. Over seven million people live in 360km2 land area and around 42% of them live in slums. Due to low economic growth, lack of infrastructure and the absence of an effective governance, Dhaka offers an unreliable waste management service to its inhabitants. The Dhaka City Corporation (DCC) is responsible for collection and disposal of 3000-4000 tons/day of municipal solid waste from the city’s 90 wards. However, DCC can collect and dispose only 40-50% of the total waste every day. As a result, the uncollected waste is primarily dumped illegally in the neighbourhood’s streets, wastewater drains, ponds, lakes etc. or managed informally causing various socio-economic and environmental problems.
Due to lack of waste infrastructure and narrow road networks, DCC do not provide any door-to-door collection system. Community based private door-to-door waste collection is one of the exceptional community participations in waste management system in Dhaka. Informal waste collection and recycling system is also another key area. There are about 120,000 people involved in the informal recycling trade chain in Dhaka City without any government funding support.
Around 83% of plastic, 65% of paper and 52% of glass are informally recycled from the waste and returned to the recycling industries. No metals are wasted and disposed to the landfill due to high economic value. Despite risky market condition for composting of waste, Waste Concern a local non-profit organisation has initiated community-based decentralized composting in 2008 by adopting low-cost technology, community participation and partnerships among various local and international actors involved. The project is registered and approved by the executive board of the Clean Development Mechanism under the Kyoto Protocol to the United Nations Framework Convention on Climate Change and is gradually scaling up.
Dhaka has many potentials to implement long term zero waste management strategies. However, there is no single solution that can be implemented within the limited economic, institutional and operational infrastructures. The following key aspects can be considered and implemented to improve current waste management systems and the vision for zero waste by 2050.
· Awareness and capacity building of the local people, waste management authority and local experts are important for implementing long term waste strategy.
· The national 3R-strategy reduce, reuse and recycle should not be limited to the policy level, instead it should foster the implementation and transformation of social perspectives on waste reuse and recycling.
· Institutionalisation and formalisation of informal waste recycling system into formal waste management system is urgent.
· Community based waste collection and composting systems should be encouraged and promoted by the local government.
· Long term waste strategy should be based on short term targets such as 70% waste collection by 2020 and 100% waste collection by 2030 and so on. After achieving a 100% waste collection system in Dhaka, more advanced zero waste goals such as zero landfill should be targeted.
· Waste diversion by informal recycling systems should be integrated with the formal systems and the recycling data should thus be recorded for the assessment of waste management performance.
· End-of-life products including electronic and hazardous waste should be managed under the extended producer responsibility scheme, Rahimafrooz battery return scheme, for instance, repaired and reused around 33,000 batteries and avoided potential environmental pollution.
· Public, private and international partnership mechanism such as the Clean Development Mechanism under the should be boosted by the local government and international organisations.