The Environmental Protection Agency (EPA) has been collecting and reporting data on the generation and disposition of municipal solid waste (MSW) in the United States for over 35 years. This extensive research is vital for measuring the success of materials management programs across the country and characterizing the national waste stream. The latest collected Facts and Figures are current through the calendar year 2018.
In 2018, the total generation of MSW reached 292.4 million tons, which translates to approximately 4.9 pounds of waste per person daily. Of the MSW generated, around 69 million tons were recycled, and an additional 25 million tons were composted. Together, this results in almost 94 million tons of waste either recycled or composted, equating to a recycling and composting rate of 32.1 percent. Furthermore, 17.7 million tons of food were managed through alternative methods, such as animal feed, bio-based materials and biochemical processing, co-digestion, anaerobic digestion, donation, land application, and sewer treatment.
Interestingly, EPA has recently begun estimating the management of construction and demolition (C&D) debris as a non-hazardous waste stream alongside the analysis of MSW. This improvement in methodology was significant enough to cause a notable rise in reported waste generation from 2017 to 2018. Therefore, waste management continues to be a high priority for local and state governments, focusing on reducing waste generation at the source and recovering waste through recycling and composting initiatives.
Combustion with energy recovery and adhering to safe landfill practices also play a crucial role in the national approach to waste management. The EPA’s non-hazardous materials and waste management hierarchy reinforces that no single waste management method is appropriate for every circumstance. The hierarchy highlights reducing, reusing, and recycling as essential practices for sustainable materials management.
Concerning the generation of MSW, the year 2018 witnessed a significant increase of 23.7 million tons over the amount recorded in 2017, bringing the total to 292.4 million tons. This marked an increase from 268.7 million tons in 2017 and a rise from 208.3 million tons noted in 1990. The increase is primarily attributed to the better tracking and accounting for various ways the food waste is managed within the food system.
Between 2017 and 2018, per capita MSW generation increased from 4.5 pounds to 4.9 pounds daily, highlighting the impact of enhanced food measurement methodologies implemented by the EPA. Materials like paper and paperboard constituted the largest percentage of MSW components, accounting for 23.1 percent of the total. This figure notably decreased from 87.7 million tons in 2000 to 67.4 million tons in 2018, indicating a significant decline driven primarily by the rise of digital news and changes in publication sizes.
Food waste was the fourth largest category within MSW, amounting to 63.1 million tons or 21.6 percent of total generation in 2018. Yard trimmings represented the next largest category, totaling 35.4 million tons, or 12.1 percent of total generation, showing a comparison to 35 million tons in 1990. The drop in yard trimmings generation can be mainly attributed to state legislation discouraging landfill disposal, encouraging source reduction methods that include backyard composting.
In 2018, plastics made up 12.2 percent of MSW generation, equating to 35.7 million tons and signifying a growth from 8.2 percent in 1990. The increase in plastics generation is derived from various categories such as durable goods, containers, and packaging. Additionally, about 2.7 million tons of selected consumer electronics were generated in 2018, contributing to less than one percent of MSW generation.
As for recycling, more than 69 million tons of MSW were recycled in 2018, with paper and paperboard representing approximately 67 percent of the recycled amount. Metals accounted for around 13 percent, while glass, plastics, and wood contributed between 4 and 5 percent each. The most recycled products included corrugated boxes, mixed nondurable paper products, newspapers, lead-acid batteries, major appliances, wood packaging, glass containers, tires, mixed paper containers, and selected consumer electronics. Collectively, these categories constituted about 90 percent of total MSW recycling.
In terms of composting and other food management strategies, the data revealed that 25 million tons of MSW were composted in 2018, comprised primarily of 22.3 million tons from yard trimmings and 2.6 million tons of food waste. For the first time in 2018, other food management methods were calculated, showing that about 17.7 million tons were handled through options that included animal feed and other innovative ways.
The section on combustion with energy recovery indicates that 34.6 million tons of MSW were combusted in 2018, where food wastage made up the largest component at approximately 22 percent. Rubber, leather, and textiles contributed over 16 percent, while plastics and paper and paperboard accounted for about 16 percent and 12 percent, respectively. Approximately 146.1 million tons of MSW were landfilled in 2018, with food being the largest component at about 24 percent. Plastics, paper, and textiles respectively comprised over 18, 12, and 11 percent of landfill contents.
Analyzing trends from 1960 to today, it’s evident that the amount of generated MSW has undergone a remarkable evolution. From just 88.1 million tons in 1960 to the peak of 292.4 million tons in 2018, generation rates have changed significantly. Particularly, generation rates decreased from 2005 to 2010 but saw a rise again starting from 2010 until 2018.
The per capita generation rate in 1960 stood at 2.68 pounds per person per day, increasing to 3.66 pounds in 1980. It further climbed to 4.74 pounds in 2000 but slightly declined to 4.69 pounds in 2005. By 2018, the per capita generation rate reached 4.9 pounds, evidencing an 8 percent rise from 2017 levels. Increased food management pathways have largely contributed to this uptick.
The rates of recycling and composting have shown improvements, rising from just over 6 percent in 1960 to about 10 percent in 1980, with further increases to 16 percent in 1990, about 29 percent by 2000, and reaching around 35 percent in 2017 before slightly decreasing to 32.1 percent in 2018.
Energy recovery from waste combustion also increased substantially from zero percent in 1960 to 14 percent in 1990, but has recently plateaued at around 12 percent in 2018. The rate of landfill utilization for waste management has decreased drastically from 94 percent in 1960 down to 50 percent in 2018.
The fluctuations in MSW generation rates are notably influenced by changes in key material categories, such as paper and paperboard, which dipped from 87.7 million tons in 2000 to 67.4 million tons in 2018. Other significant shifts included the consistent increase in food waste generation since 2000. Overall, MSW generation continued to rise from 1960 through 2005 but faced a slight rollback from 2005 to 2010, recovering from 2010 onward.
The recycling and composting rates across various MSW materials have seen significant increases over the last 58 years, affirming that recycling (including composting) did not exceed 15 percent until 1990. Major developments in recycling rates occurred until 2005, but have since plateaued. In fact, the recycling rate was 32.1 percent in 2018, which represents a slight decline from 34.7 percent in 2015.
A detailed analysis shows that by the year 2018, the recycling or composting rates for categories such as paper and paperboard, yard trimmings, and food were notable. Paper and paperboard’s recycling rate in 2018 was 68.2 percent, while yard trimmings composting was rated at 63 percent. Comparatively, food and other MSW organics composting was recorded at 4.1 percent, consistent from the previous year despite an increase in food waste generation estimates due to methodology changes.
EPA’s report also highlights significant greenhouse gas benefits resulting from sustainable materials management. The agency’s emissions reduction calculations, as part of its Waste Reduction Model (WARM), estimate that recycling, composting, combustion with energy recovery, and landfilling of MSW in 2018 saved over 193 million metric tons of carbon dioxide equivalent (MMTCO2E). This achievement can be likened to removing nearly 42 million cars from the roads for a year.
Among the recyclable materials, paper and paperboard recycling alone accounted for over 155 MMTCO2E in reductions, equating to the emissions from more than 33 million cars removed from the roads. The environmental benefits are evident and showcase the importance of effective waste management strategies in combating climate change.
Continuing efforts to reduce waste and enhance recycling rates must remain priorities for the future, as the data demonstrates both progress and ongoing challenges in realizing sustainable waste management in the United States.
image source from：https://www.epa.gov/facts-and-figures-about-materials-waste-and-recycling/national-overview-facts-and-figures-materials
