Effective waste reduction, collection, management and recycling of materials is crucial to ensuring urban sustainability. Urban systems will not be sustainable until materials and waste products are properly handled, especially given their high consumption and disposal rates. Each day, over six million tons of municipal solid waste are generated from cities worldwide. Without planning and technology intervention, the volume could grow rapidly. The per capita waste generation rate in the United States., measured in various terms and literature, is one of the highest compared to other developed economies. In other words, there are potential opportunities for improving the efficiency of waste and recovery systems without compromising the rate of economic development. In fact, resource recovery and reuse activities create new businesses and jobs, and therefore, promote sustainable economic development.
The environmental impacts of material and waste management (MWM) activities can occur locally (e.g., noise and land use changes), while other associated impacts can be regional or even global (e.g., water contamination, air quality, and climate change). Globalization further shifts the impacts of MWM from developed countries to developing countries, where environmental regulations may be less stringent. All MWM activities generate negative impacts that need to be mitigated, but the magnitude of environmental stress and pollution from final disposal activities (landfills and incinerations) are far greater than methods such as composting and recycling. An estimated 10 to 15% of global greenhouse gas emissions could be reduced by landfill diversion, material recycling, and energy waste recovery through the MWM lifecycle (UNEP 2015).
Timely and effective MWM is needed not only to minimize the end-of-pipe effects of socioeconomic activities, but also to meet the required goals of health, sanitation, cost efficiency, ecosystem sustainability, social equity, and resource and infrastructure resiliency. This can only be achieved through the life cycle of materials as well as of various types of MWM infrastructure. MWM spans temporal and spatial boundaries and naturally interacts with other sub-systems in urban areas, such as energy, water, transportation, and infrastructure.
Sustainable MWM necessitates a transformation from the “out of sight and out of mind” waste-disposal paradigm into resource/material-centered strategies. Fundamentally, sustainable MWM requires transparent, high-quality, and region-specific data for program design, implementation, and assessment. Emerging technologies, including information and communications technology (ICT), renewable energy fleets, and innovative engineering solutions, offer opportunities for more efficient MWM, holistic system planning, and meaningful stakeholder participation as well as citizen education.