Before & After Green: 9th Avenue USPS Building

Update, July 19, 2010: Thank you to @NYCWW for information regarding the plant palette of the green roof.  We gathered information about the project's plants from several news sources and a USPS fact sheet.  The plants on the roof are not native.  From NYC Wildflower Week: "re: largest green roof in NYC: those are NOT native plants. They are the names of cultivars of exotic sedum."

Before (screen capture of Google Maps)

After (Image courtesy of a reader)

One of our readers alerted us to the presence of a green roof on the Postal Service mailing facility at 341 9th Avenue. The green roof was revealed in July 2009 and was covered by several news outlets such as Fast Company, City Blog, Tree Hugger, Inhabitat, and Environmental Leader.  The 2.5 acre site provides passive recreation for postal employees as well as environmental services.  What environmental services does the roof provide?

• 75% reduction in stormwater runoff during the summer (Fast Company; Environmental Leader)
• up to 35% reduction in runoff in the winter (Environmental Leader)
• $30,000 savings in heating and cooling costs (Fast Company) or 30% energy reduction by 2015 (Environmental Leader)

According to a USPS project fact sheet, the plant palette is comprised of regional native species several non-native sedum cultivars such as Coral Carpet, John Creech, Weinhenstephaner, Immergrunchen, Fudaglut, and Red Carpet. The Times City Room blog reported that the cost of the project was $30 per square foot (engineered soil costs $120 per cubic yard compared to $2-$3 per cubic yard for normal soil). The landscape architecture studio for the project was Elizabeth Kennedy Landscape Architects of Brooklyn, NY.  World Landscape Architect interviewed Elizabeth Kennedy in July 2009.