Food waste includes uneaten portions of meals and trimmings from food preparation. It is the largest component of generated waste by weight. Because of its low composting rate, food waste is the largest component of discarded waste by weight.
Estimates of the amount of food waste vary widely. EPA estimates that each of us discards less than a pound (lb.) a day or 223 lbs. of food waste a year. But a study by the University of Arizona Garbage Project shows a per person food scrap rate of 1.3 lbs. every day or 474.5 lbs. per year. The U.S. Department of Agriculture also shows more food waste than EPA, estimating that higher percentages of fresh fruits and vegetables, dairy, and grain products are wasted than meat, dried beans and nuts, and processed foods.
More than 60 million homes and 500,000 businesses have in-sink food disposers that divert food waste from landfills. Curbside collection of food waste for composting is found in about 100 North American communities. Large-scale projects in Toronto, Seattle and San Francisco collect and compost food waste effectively, but cost, facility siting and vectors are issues for new projects.
Food waste’s share of the solid waste stream increased by 2 percent from 1960 to 2009. During the same time, increased package and paper recycling caused food waste’s share of the disposal stream to increase by 41 percent.
Food Waste MSW Facts
- 34.29 million tons, or 14.1% by weight.
- 223 pounds (lbs.) per person per year.
- Food waste is 70% water, 30% solids.
- 850,000 tons, a 2.5% recovery rate.
- Grocery store food processing trimmings are a prime resource for composting facilities.
- 100 cities and counties collect food waste for composting.
- Most of the programs are on the west coast and in Canada.
- Composting is the controlled decomposition of organic matter by microorganisms into a humus-like product by generating heat and energy to destroy weeds, plants and human pathogens.
- Backyard compost piles that include food wastes must be tightly controlled to eliminate pests.
- Tipping fees usually charged for incoming food waste.
Incinerated or Landfilled:
- 33.4 million tons, or 20.8% of discarded MSW by weight.
- Usually the wettest component of MSW with moisture content of 70% and BTU value one-third of MSW.
- 21.4 million cubic yards or 5.3% of landfilled MSW in 1997.
- Food waste can decompose into methane in a landfill.
- Landfilled food waste weighs 2,000 lbs. per cubic yard (lbs/cu.yd.).
- Food scraps, solid and liquid fats weigh 412 lbs. in a 55-gallon drum.
- Packaged foods create less food waste.
- In-sink kitchen disposal units divert food waste to wastewater treatment plants. In many cases, these facilities produce fertilizer or biosolid products.
End Market Specifications:
- Each facility has its own specifications. Non-organic materials such as metals and plastic must be kept out.
Biocycle Magazine, www.jgpress.com
Composting Council of Canada, www.compost.org
Cornell Waste Management Inst., www.cwmi.css.cornell.edu
“Municipal Solid Waste in the United States: 2009 Facts and Figures,” U.S. EPA, Office of Solid Waste, www.epa.gov/osw
National Recycling Coalition, Measurement Standards and Reporting Guidelines, Washington, www.nrc-recycle.org
U.S. Composting Council, www.compostingcouncil.org
*Data is from 2009 EPA estimates, except where noted.