Quantifying Urban Agriculture Impacts, One Tomato at a Time

With most of the world's population living in urban areas for the first time in history, understanding food supply in urban areas is becoming increasingly important. With the resurgence of the local food movement, urban food production in the form of personal, institutional and community gardens, rooftop gardens and urban farms, are emerging as a popular activities. For the past five years major urban areas have again been starting to recognize the potential of urban food production and consider ways to support it. The list of examples is endless.

Last year, for example, a bill to change San Francisco’s zoning code to allow urban agriculture across the city and legalize the sales of foods produced in urban gardens was passed by the Board of Supervisors. In 2010, a report by the Manhattan Borough President recognized personal, community and commercial urban agriculture and urban food production as the first goal in strengthening the local food system of New York, and the city’s Council speaker (and now mayoral hopeful) Christina Qunin introduced FoodWorks: A Vision to Improve NYC’s Food System. In addition, a report by the Urban Design Lab at Columbia University sorted through available land in NYC with some 29,000 lots of vacant and underused land to evaluate its effectiveness for urban agriculture.

 In Philadelphia, the city included urban food production in the actionable goals of its sustainability plan, Greenworks Philadelphia. The Seattle city council passed a resolution “establishing goals, creating a policy framework, and identifying planning, analysis and actions for the purpose of strengthening Seattle's food system sustainability and security” and approved a bill that supports the rapidly growing local food movement in the city. The ordinance updates the city’s land use code governing urban agriculture uses, including allowing "urban farms" and "community gardens" in all zones, and allowing residents to sell food grown on their property. And it's not just big cities that are leading the way. Three towns in Maine, Sedgwick, Penobscot and Blue Hill passed a food sovereignty bill last year.

With all this activity and much more that is happening all across the U.S., we still know little about many dimensions of urban agriculture such as their capacity to produce food and provide other important ecological and cultural services. On the food production front there is some good news. New efforts to measure and estimate production in community gardens are starting to develop. An early effort in 2009 by UPenn professors Vitello and Narin resulted in a methodology that prompts urban gardeners to weigh their produce. Based on measurements in six community gardens, that study estimated that community gardens in Philadelphia produce over 2 million pounds of produce annually with total dollar value of fruits and vegetables at $4.9 million. Following their footsteps, but with a NYC approach, Farming Concrete, a 3-years old grassroots science project is measuring food production in community gardens in the city. Farming Concrete works with gardeners and provide necessary resources (such as scales, record keeping materials and training) so gardeners can easily keep track of their production. Last week, they released their 2011 report, with 43 participating gardens, Farming Concrete estimates they grew 17,000 lb of produce with value of $52,000.

Why it is important to know how much food is produced in urban gardens? In general, urban food production could only put a small dent on the urban food consumption landscape. However, Farming Concrete and others argue that understanding the quantitative aspects of urban food production helps highlight them as important part of the urban fabric and provide legitimization for gardeners. In the case of Farming Concrete, it also helps further the notion of citizen science and grassroots research.

There are also other reasons to look closely at urban food production. With many cities adopting sustainability goals, trying to address environmental issues of today and risks of the future, urban gardens are one of these unique urban landscapes where positive social and ecological processes intertwine. Cities are just now beginning to contemplate the fact that there are many tradeoffs in every sustainability decision they are making. For example, as part of PlanNYC, a big plan to mitigate adverse impacts of runoff from rain events is proposing green infrastructure as a major way to contain rain and reduce CSO flows.

As my good colleagues Nevin Cohen and Kubi Ackerman argued recently in a column posted by Mark Bitman there is a “clear win-win” situation with many communities at the crux of CSO discharges and limited access to fresh and healthy food. Community gardens and urban food production should become a priority for green infrastructure development. Measuring their impacts is a crucial step to making this happen. Measuring food production is one good way to start. After all, the local food revolution needs not just a strong regulation to back it up, but also sufficient data to show all the skeptics it is a viable strategy.

[Image credit: Vibrant Notions, Flickr Creative Commons]

Peleg Kremer is a Post Doctoral Fellow at the Tishman Environment and Design Center at The New School. Her research focuses on urban social-ecological systems, ecosystem service and urban food systems and she teaches at the New School's Environmental Studies program.