As the climate crisis makes its way into more and more headlines and also into the collective consciousness, many cities in the US have begun the push towards the goal of sustainability. This is especially significant given that by 2050, 68% of the world’s population will call themselves city-dwellers, and that cities are responsible for a significant amount of resource use and carbon emissions. Many of the plans and pledges these cities create in the name of sustainability are ambitious and can often seem unrealistic. But researchers in Phoenix, AZ have recently published a study that suggests agriculture may be the key to reaching urban sustainability goals. That’s right, folks, agriculture doesn’t just happen in places like the ones you see out the window of your station wagon as you head out of town on the family camping trip you dread every year. It can happen in cities, backyards, and as these researchers discovered, in previously underutilized city spaces that are often overlooked. Phoenix, like many other cities, has a set of 2050 Sustainability Goals. Researchers have found that if the city maximizes its capacity for urban agriculture, some of the city’s major sustainability goals like the elimination of food deserts, access to green space, and reductions in energy use and carbon emissions can all be reached.

This conclusion was reached by combining these city-specific goals with analysis of detailed data. Three types of urban infrastructure were considered as potential spaces for urban agriculture: vacant lots, flat rooftops, and building facades, all of which make up about 7.1% of the land area in Phoenix. What’s great about this is that these spaces aren’t normally utilized, and therefore urban agriculture hubs wouldn’t be replacing anything, but enhancing something that already exists. It was found that if all these spaces were used to grow food, 183,000 tons of food per year could be produced. Better yet, these urban farms would also be providing local, fresh food to all of the food deserts (areas where many residents do not have a car and where a grocery store selling healthy foods is more than a mile away) in the city.

Researchers found that urban agriculture would not only help eliminate food deserts, but would also provide green space for many communities that don’t currently have access to it. It was discovered that block groups in Phoenix that do not have a park or green space access would drop dramatically from 78% to 31% with the addition of urban farms. In terms of electricity consumption and carbon emissions, researchers found that by growing food on city rooftops, buildings would be better insulated and would need to use less

downtown Phoenix, AZ

A view of downtown Phoenix, AZ, where researchers have identified vacant lots, rooftops, and building facades as potential sites for urban agriculture.
Photo by Stephen Zank, licensed under CC BY-SA 2.0

electricity, therefore also decreasing their carbon footprint.

If you’re worried about how all of these fruits and vegetables are going to be watered in a desert city, don’t be too concerned. Agriculture offers lots of opportunities to use recycled water, and the estimated water consumption of urban agriculture in Phoenix was similar to the amount people already use for their lawns and swimming pools. If city residents used that water instead to grow food, the city would still be consuming a similar amount of the precious

resource. Researchers found that a bigger constraint for urban agriculture is city zoning, the price of land, and land ownership versus public ownership.

This research suggests that cities around the country, and the world really, should consider how urban agriculture can be fully utilized in city spaces, and what kind of environmental as well as social benefits residents can enjoy if urban spaces are used to grow more food.

Journal Article:

Aragon, N.U., Stuhlmacher, M., Jordan, P.S., Clinton, N., and Georgescu, M. 2019. Urban agricultures bounty: contributions to Phoenix’s sustainability goals. Environmental Research Letters 14(10).