Cover Photo: New York City Steady State Refurbished Buildings (Source: NYC (Steady) State Tumblr)

I am currently studying to get a Master's degree and I am taking a course on sustainability at the moment. Every week the professor assigns us readings to do and gives us a question to write a personal response about after the readings. I will be posting these after they are handed back to us to make sure everybody in the class has handed them in. This week, we read:

  • Food-miles and the relative climate impacts of food choices in the United States by C.L. Weber and H.S. Matthews (DOI: 10.1021/es702969f, free)
  • Carbon footprint of nations: A global, trade-linked analysis by E.G. Hertwich and G.P. Peters (DOI: 10.1021/es803496a, free)
  • Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply (USDA and DOE, free)
  • How Green Could New York Be? by Maria Konnikova (New Yorker, free)
  • On front lines of recycling, turning food waste into biogas by R. Cernansky (YALE environment360, free)
  • How weeds could help feed billions in a warming world by L. Palmer (YALE environment360, free)
  • How to make farm-to-table a truly sustainable movement by D. Toomey (YALE environment360, free)
  • Ch. 13, "Mining Australia" in Collapse by Jared Diamond (although I'll admit I didn't read this one)

Note: The actual prompt was "A tree may grow in Brooklyn, but can you actually farm in Manhattan? Rethink the technical limits and boundaries of agriculture -- how local can we make it?", but my CMS (Ghost) doesn't allow titles that long, probably for good reason.

Michael Sorkin's New York City (Steady) State project makes it clear that energy use provides a hard limit to the amount of produce that urban farmers can grow, but it also makes it clear that people living in urban environments can grow a significant portion of the food they consume. Admittedly, there are several social issues that Michael Sorkin does not talk about in either the New Yorker article or Arch Daily involving property rights and responsibility. Urban Farming is about more than just food sources as growing some produce in the city reduces the load on farms so they can either return to natural land or farmers can grow crops for biomass on them.

In the early 1900s, visions of future New York City had sky bridges connecting all of the different buildings and giving the city more open space through the vertical use of the areas above roads. At the time, it made sense since elevator's were not common, cheap, or reliable so walking all the way down to the bottom of a building just to the top of the next one seemed ludicrous. The biggest problem was that most of these buildings have separate owners. The few sky bridges that remain in Manhattan are mostly between buildings that had a common corporate owner when they were built and even those have fallen into disrepair.

What does this have to do with urban farming? In order to have the vertical farms and internal greenhouses, building owners will have to agree to give up space to the government. Given there is such a premium on square footage in New York City that engineers actually code optimization problems for the layout of staff in offices just to maximize usable space per dollar, it is unlikely that companies would be willing to give up some of their space to a greenhouse. On top of that, Chef Dan Barber wrote about the complexities of sustainable farming and how you have to have deep understandings of several different systems in order to keep soil healthy without fertilizer and have demand for the rotational crops. In order to do urban farming on a scale that can even provide for 30 percent of New York City, it will be necessary to have full-time gardeners.

So far though, I have assumed that all benefits from urban farming come from the produce they create when there are several other reasons to at least work towards community gardens and covering some exterior cladding with plants. Community gardens are a fantastic way to foster connections between neighbors in a city where it is rare to do this. Urban farms and gardens present a fantastic opportunity for education to help people understand where their food comes from and to drive up demand for sustainable goods. Improvements to air quality and aesthetics can also make a noticeable difference, particularly in less affluent areas. Community gardens would also give people living in the city the chance to experience the outdoors which I believe is important. I have met so many New Yorkers who had never been hiking before who were well into their late twenties.

However, from a pure sustainability perspective I am not sure how much benefit local farming would provide. Looking at Food-Miles and the Relative Climate Impacts of Food Choices in the United States, transporting products is not really that significant a portion of the greenhouse gas emissions from food. It is far more important to make farming more sustainable and to cut back on red meat than it is to eat local. As the paper points out, shifting one day of eating red meat to eating fish or chicken more than makes up for eating from local farms. Reducing food waste in the United States would also go a long way towards increasing sustainability given that a lot of emissions from farming are because farmers are creating extra food just for it to end up in a landfill.

To move away from the doom and gloom, I think there is a lot of value in trying to build community gardens and vertical farms in cities that are far less dense or far less expensive per square foot than New York City is. There are a lot of positive externalities associated with urban farming that do not show up in the standard metrics, just like how sustainable farms produce far less of a specific crop even if they produce more overall. Minneapolis has an extensive network of bridge tunnels through the downtown because the government was intimately involved in the planning details. The government also sold the idea to land owners because they could recoup some costs by having coffee shops and restaurants on these levels. Overall, I think urban farming is a tremendously useful tool, it cannot solve the issues with current city design by itself.