10.7 Food, resources, and waste management

The 56% of humans who live in cities consume 75% of all the natural resources we use as a species and produce half of all our waste. ^[1] We have a long way to go in increasing the efficiency of how we use resources, so that we consume less in the first place, and improving how we manage things we’re done using, so that not so much of it goes to waste.

Food waste and food deserts in cities

A huge part of this body of resources is food. Globally, about one third of all food produced goes to waste (Fig 1). That’s one third of all the resources put into growing plants and raising animals wasted, one third of all the time, energy, and space used to store and transport the food wasted, and one third of food that could’ve been eaten rotting and releasing greenhouse gases in the process. At the same time, hunger is a massive problem around the world. One out of every eleven people on earth were undernourished as of 2023. ^[2] We produce more than enough food to feed all of them, but waste is great enough to create hunger.

In many cases, food goes to waste because it isn’t packaged or stored properly and so goes bad, but single-use food packaging is also a massive source of waste. For the food that does need to be thrown away, composting is much better than putting it in the trash. Not only can it be turned into valuable fertilizer, but in the composting process, food decomposes aerobically, producing carbon dioxide, whereas in landfills, it decomposes anaerobically and produces methane, which is a much more potent greenhouse gas. In the US, food waste makes up 24% of landfill contents. New York City in the US requires businesses and individuals to compost yard and food waste ^[3] and is working to educate residents on the process.

For many people, the problem with food access is not that they can’t get enough calories, it’s that they only have access to unhealthy, processed food. Areas of cities with low access to affordable, healthy food are known as food deserts.

Policy approaches can shrink food deserts, including incentives for grocery stores to open locations in food deserts and improved public transportation between low-income neighborhoods and grocery stores. ^[4] Cities can also address this issue through urban agriculture, which is growing in popularity around the world. Community gardens can be set up in empty lots and on rooftops and provide fresh produce to people living nearby. As mentioned previously, high diversity of plant species in gardens and other urban greenspaces supports the pollinators that many food crops depend on. The city of Rosario, Argentina has a program that has trained thousands of families and dozens of schools on agricultural skills, and many of those people have gone on to start vegetable gardens. ^[5] And in Seoul, South Korea, a small company partnered with the metro to create an LED-lit, vertical hydroponic farm in a station, as well as information about urban agriculture and multiple cafés in other stations.

Resources and Waste in Cities

Modern societies also use non-food resources in inefficient and wasteful ways. Consumer culture incentivizes businesses to produce low-quality products that will need to be replaced often and encourages individuals to buy things they don’t really need. In contrast, a circular economy, based on how ecosystems function, would use resources efficiently without producing waste or pollution (more details in a short article click here and 4-minute video click here). The first two steps toward this goal are to reduce consumption in the first place and to reuse as many things as possible. The growing sharing economy allows people to sell or give away items they no longer need and to seek out used items instead of buying everything brand new.

Cities may have limited power to influence business practices, but they can help provide alternatives to continuous consumption. Around the world, people are starting libraries of things, which can include items like tools, games, kitchen equipment, musical instruments, computers, and sports gear so that people who can’t afford or have no reason to own something long-term can use it when they want to and then give it back for others to use (Fig 2). Cities can also facilitate reuse of things like clothes and furniture by hosting swap events and locations. Belo Horizonte, Brazil has a Computer Reconditioning Center where low-income residents are trained to refurbish used IT equipment. The computers and other items then go to ‘digital inclusion sites,’ offering free computer use and internet access to people around the city (details and impressive stats click here). For more ideas of how cities can promote reuse and repair, you can check out C40’s implementation guide.

As a last resort if an item must be thrown away, recycling (and compost for food) are the best option. However, at least in the United States, people have attitudes and beliefs about recycling that do not lead to useful behavior. For decades, the plastics industry promoted recycling as the solution to plastic waste, despite knowing that producing new plastic is cheaper than recycling it and so recycling would not solve anything. ^[6] Instead of taking responsibility for all the trash they were producing, companies used this misinformation to put the responsibility on consumers. To this day, many people believe that it doesn’t matter how much plastic they consume as long as they recycle it afterwards. What’s more, people don’t recycle properly at all. Only about two thirds of paper and paperboard waste in the US gets recycled, and the rest makes up 12% of the contents of landfills. ^[7] The solution to all of this, instead of asking consumers to be aware of and responsible for disposing of all their waste properly, is to incentivize businesses to reduce waste and create easy-to-use recycling and compost infrastructure. Cape Town, South Africa created a program to match companies based on materials they use and produce: one’s waste products are another’s raw materials, so they exchange instead of throwing them away. ^[8] A pair of companies in China is working not only to recycle materials from batteries, but improve battery design so they last longer and are easier to disassemble for components. ^[9]

Only 19% of the world’s municipal solid waste gets recycled (UN GWMO), and dealing with the remaining 81% is where waste management comes in: making sure the waste goes somewhere where it will stay contained and won’t contaminate the environment. Globally, 700 million people in urban areas don’t have waste collection services (Fig 3), and only 20% of waste workers have formal jobs, like city-paid trash collectors. The rest work independently, doing things like salvaging usable materials from landfills.

Accra, Ghana created a program to train informal waste workers and formalize the waste management industry. This not only improved their working conditions, but also increased waste collection from 53% to 90% and recycling rates from 5% to 18%. ^[10] Curitiba, Brazil has neighborhoods that municipal waste vehicles can’t access. They ask residents in these areas to bring their waste (sorted into compostable and non-compostable) to designated collection points, offering bus tickets and fresh produce in exchange for the waste. ^[11]

Knowledge Check

Take a moment to complete the short quiz below to assess your understanding of this section. Read each question carefully and refer to the section content as needed. This quiz is not graded – it’s simply an opportunity for you to reflect on what you’ve learned and reinforce key concepts.