Green Roofs and a Green Future in the South BronxJune 30th, 2011 | Posted by in Air Quality | Design | Environment | Gardening | Green Building | Water Conservation
In terms of sustainability and reducing one’s impact on the environment, living in a city can have – perhaps surprisingly – distinct advantages over living in the suburbs or countryside. New York City, in particular, is consistently ranked as one of the most energy-efficient places to live in America, thanks to our proliferative public transportation system, reliance on natural gas as our primary energy source, walkability, and mixed-use zoning laws. Indeed, an average New Yorker’s carbon footprint is about one-third that of an average American.
I don’t meant to offer unqualified praise of New York City and its efficiency, because there are significant environmental drawbacks to living in a large city, as well. The issues we face in New York are substantial: lack of access to green space; the relatively long distance food must travel to feed our massive population; elevated asthma rates, especially in children; the urban heat island effect; and severe water pollution from heavy rains, thanks to our combined sewage-storm water pipes.
But fortunately, different governmental, nonprofit, and civic organizations are working to address these issues, and Sustainable South Bronx is one of them.
In particular, Sustainable South Bronx (SSBX) is working on the expansion of green roofs – the environmentally- and socially-beneficial effects of which are substantial and numerous.
Green roofs, in their most basic form, are living vegetation systems, or gardens, on the roofs of buildings. They come in numerous forms, shapes, and sizes, but this is one of their great strengths – they can be adapted to function in nearly any scenario, providing substantial benefits to the buildings and communities where they are located.
Typically a green roof consists of an impermeable membrane across the surface of the roof. On top of this is placed a drainage layer, a filter fabric, a lightweight growing medium, and finally vegetation. Roofs which are capable of bearing very heavy loads can support even trees and large shrubbery; roofs which are a little weaker typically support lighter-weight flora like grasses and wildflowers.
The benefits are indeed surprising, and actually mitigate many of the urban environmental issues I listed above – even childhood asthma rates. Green roofs provide insulation from the sun, and lower the temperature of the building, reducing cooling costs in the summer, and reducing heat loss in the winter. They also perform important functions for the urban water cycle: green roofs absorb rainwater, preventing excess water from running directly into the sewage system which exhausts into local waterways (including the East and Hudson rivers in NYC). Green roofs also reduce the urban heat island effect through natural shading, insulating, evaporative and evapotranspirative properties. They also provide more green space to area residents, and reduce air pollution by trapping particulate matter, and reduce greenhouse gases by absorbing more carbon dioxide. To read more about the numerous benefits of green roofs, feel free to read this report by Sustainable South Bronx on the urban heat island effect. [PDF].
SSBX was founded in 2001 by environmental justice activist Majora Carter. SSBx actually built the first green and cool demonstration roof in NYC above their offices in the Bronx; in 2007 they expanded their mission to a for-profit green roof installation company, Smart Roofs LLC. But what is perhaps most innovative about SSBx’s approach to sustainable community development is its keen awareness of the intersection of social issues and environmental issues, the hallmark of an environmental justice approach. To that end, SSBx has built green roofs with the community in mind, for the purpose of increasing green space in one of the most dense city neighborhoods, with the least access to green space.
And not only does SSBx support the expansion of green spaces throughout the Bronx, they do so through community green job training programs, boosting employment and worker activity, while at the same time improving the health of people and the environment in one of the most underprivileged and polluted parts of New York City. The Bronx Environmental Stewardship Training Academy (BEST) is one of the city’s most successful green collar training programs. The program has trained numerous people who continue the upkeep of other SSBx projects – like the Bronx Greenway, where they have planted and continue to maintain over 400 trees.