A New York City postal processing facility that was contaminated during the 2001 anthrax attacks is now the site of the largest "green roof" in Manhattan.

The 65,000-square-foot roof area at the Morgan Processing and Distribution Center on Ninth Avenue between West 29th and West 30th streets cost $5 million to install in 2008. It affords views of such landmarks as the Empire State Building and is one of several pilot green roofs in the metropolitan area. During the anthrax attacks, the Morgan facility was one of 23 U.S. Postal Service facilities to be contaminated, according to a 2004 U.S. Government Accountability Office report. The site remained open for work during decontamination (as a processing facility, it is not open to consumers), but most of the site's 5,000 employees received precautionary antibiotics. Today, security at the facility is tight, but the seventh-floor green roof is open for employees to visit on breaks.

The Morgan facility's green roof and other new energy-saving measures there, such as replaced windows, have saved the Postal Service more than $1 million in energy expenses so far, Tom Samra, Postal Service vice president of facilities, said in a prepared statement. The location is on track toward a target to reduce storm water runoff by 75 percent in summer and 40 percent in winter, he added.

New York City has an estimated 1 billion square feet of roof space, according to Columbia University climate scientist Stuart Gaffin, that could be converted from black tar to "green," which is just one solution to the problems that conventional city roofs generate—they contribute to the urban heat island effect by storing and trapping solar energy and they collect storm water that ends up overwhelming the city's sewers and thereby polluting the waterways surrounding the city.

Buildings contribute 80 percent of all the greenhouse gas emissions in New York City mainly as a result of their associated electricity consumption, burning of fuel oil or natural gas to provide heat in the cold months and burning of non-electric cooking fuels such as gas. "We should think of them as polluting devices just like we think of automobiles, in terms of the climate problem," Gaffin says.

New York's Mayor Michael Bloomberg has committed city funds to converting some of the area's black tar and stone roofs into highly reflective white roofs, which reduce temperatures on roofs and cooling costs but fail to address the storm water runoff problem. So-called blue roofs, in which water drains are slowed down, are proposed by some to deal with the latter issue, Gaffin says. U.S. cities that have more aggressively embraced green roofs include Chicago, Seattle and Portland.

Gaffin is collecting data on all these approaches, as well as easy-to-install tray systems for green roofs, to see which are the best for decreasing a roof's temperatures and runoff.

Other green roofs have been installed at the Bronx County Courthouse (10,000 square feet), Ikea in Brooklyn (70,000 square feet), Ethical Culture Fieldston School (two roofs, measuring 5,100 square feet and 1,500 square feet, in the Bronx), a Con-Edison building in Long Island City (a quarter of an acre, or about 10,000 square feet) and Hackensack Hospital in New Jersey (about 5,000 square feet). All these projects will be eclipsed in size by a seven-acre green roof project set to go atop the Javits Center within the next two years.

Green roofs typically feature plants in a growing medium made of inorganic heat-expanded shales and clays that become very lightweight and porous so they can retain a lot of water. Plant roots adapt to these high-mineral-content media that are much lighter than conventional topsoil.

The lightest professionally installed roofs involve a four-inch planted medium on top of several layers of protective membranes atop the original roof. The layers start with a waterproof membrane (possibly PVC) other than the roof itself, then a geotextile filter cloth to prevent the medium from penetrating too far down, a root penetration barrier, a drainage layer, a second geotextile cloth for water retention, the rooftop growing medium and finally drought-tolerant vegetation.

To get the 2,000 cubic yards of growing medium required up to the seventh-floor roof of the Morgan facility, Tecta America's Brian Singley worked with specialized sub-contractors to devise a new approach. The team loaded the medium, which had been dumped by trucks into a holding pen constructed on West 30th Street adjacent to the postal facility, into the hopper of a large vacuum truck that is normally used to remove stones from roofs. By reversing the suction on the vacuum, the medium was blown onto the roof.

View a slide show of plants and vistas at the Postal Service's Morgan facility "green roof"

10 Comments

1. 1. Philopeantube 12:27 PM 8/23/10

   Green Roofs, although a step in the right direction really just mask the problem of pollution and destruction by industrialized civilization. We need to understand the simply placing plants on roofs is not going to save our planet from human destruction.

   Reply | Report Abuse | Link to this

2. 2. vagnry in reply to Philopeantube 02:54 PM 8/23/10

   If your boat capsizes ½ mile from land, a single breaststroke won't save you, so why bother?
   
   No one, to my knowledge, has ever claimed green roofs would save the planet, but maybe it could give ½ % of what we need to do!
   
   

   Reply | Report Abuse | Link to this

3. 3. Bops 08:14 PM 8/23/10

   It's also a nice garden to visit in a place like New York.
   No one has suggested that it's the answer to pollution, it does reduces the cost of heating and cooling the building.

   Reply | Report Abuse | Link to this

4. 4. TonySal 11:38 PM 8/23/10

   Since it does reduce the cost of heating and cooling the building, it follows that it must reduce the greenhouse gasses produced. It may not be a large amount but, each grain of rice adds a little to the rice bowl.

   Reply | Report Abuse | Link to this

5. 5. Science-faction in reply to Philopeantube 07:12 PM 8/24/10

   Philopean wrote, in part: ...mask the problem of pollution and destruction by industrialized civilization...
   
   I suggest that his/her post is less about whether or not green roofs even help than it is about looking face-on at the essentials. In this case it may be urbanization and all that this does to change how humans live on the face of the earth and thus how we change where our food comes from, how plants & animals live in the 'nature' that humans leave for them after changing the nature of the very ground they live on (well, ok, the air AND the water too.... GRIN).
   
   However, I suggest we are just another animal species and we have re-formed earth's fabric to support our species' lifestyle, just as beavers, locusts, starlings, horseshoe crabs, kelp, pine forests etc. do. So the difference is that WE can see what we do, what we have done and what the future holds if we keep on w BAU (Business As Usual).
   
   So imagine we become nearly 100% sun & wind powered; that we put virtually all rainfall back into the ground at least as clean as it was when it fell on our cities & other disruptions; that we respect the fabric of gaia's systems (bio and non-bio!) as elements of a temporary but long-lived integrated balance; that we grow our buildings with solar-smart living skins, roof them with energy saving, air-cleansing and food producing materials; etc.
   
   Then our presence, our post-INDUSTRIAL presence, becomes part of the living earth rather than an attempt to pave it over and tamp it down flat.
   
   Such is the scale of a more successful perspective  not an incremental one, not a fretful one, but rather a realistic one that thrives in another perspective that most agree differentiates humans from what we know of the rest of the biological world: in hope, which guides our version of the universal 'survival instincts' shared by all earth's species.
   
   We must never treat things, such as 'green roofs', as separate from the interactive, interdependent whole we used to just call 'this world'. Green roofs must NOT be a fad, a design option, nor a mask. I urge any reader to consider methods now available to live consciously instead of conventionally - - Transition Initiatives, Earth Charter communities, urban eco-villages aka Eco-Cities, and other such real-world socio-spiritual-ecological-economic systems. Can't you just see the next plain of our gradual ascent from the Rift Valley?
   
   Bill Marston, LEED-AP; Adj. Prof. of Sustainable Design Master of Science degree program; Green Advantage� instructor
   Philly

   Reply | Report Abuse | Link to this

6. 6. amalone 05:28 PM 8/25/10

   Check out a video tour of the green roof, so beautiful!: http://construction.com/video/?fr_story=3a250c134560abab2b4102d3ec9d4b4cd82a56ac&rf=bm

   Reply | Report Abuse | Link to this

7. 7. Helen 06:13 PM 8/25/10

   Just having a green space within a city is a blessing for those of us who have been born in cities. The step is really great if you work at the building and have a rooftop garden to retire to during breaks and lunch. There are no jobs in rural areas, I know because I left Phila. for a rural Penna. county. This rooftop gardening happened in Harrisburg when an employee of OIC collected old crates, kids swimming pools, etc. and found someone to bring in soil. It was refreshing though limited and did provide some alternative food for the poor. Baby steps but helpful to those who can take advantage of the beginning changes.

   Reply | Report Abuse | Link to this

8. 8. LKeenan 11:15 AM 8/26/10

   Green roofs help. On a hot day, would you rather stand on a grassy field, or stand in a parking lot? Use this same logic for a green roof. They can help abate the Urban Heat Island effect, by also reducing the energy used by HVAC units. If the units are on a rooftop sucking in air that's 140 degrees off a dark rooftop, and needing to cool it to 70 degrees, that's using a ton more energy than would be needed while taking in air from a green rooftop. On avg., on a 90 degree day, a green roof is 95 degrees ambient air temp, and a conventional rooftop is 140 degrees. Big difference. There's still a long way to go, but green roofs are a start. Hats off to USPS for sustainability efforts.

   Reply | Report Abuse | Link to this

9. 9. Wayne Williamson 02:37 PM 8/28/10

   excellent article...on the other hand putting 7k square meters of solar cells would provide about (7000(square meters)*100(watts per square meter)*5(hours of sun) would produce around 3.5 mega watts of energy per day....then again it would not reduce the heat island effect....

   Reply | Report Abuse | Link to this

10. 10. MendelPotok 01:00 PM 7/6/11

    There is a psychological aspect to a green roof that shouldn't be ignored. Seeing a spot of green in an otherwise utilitarian section of town could inspire more environmentally conscious behavior, if only to preserve the added beauty.
    
    http://www.scenariovpd.com

    Reply | Report Abuse | Link to this