News Brief

"Blue Roof" Adds Stormwater Detention Alongside Green Roof in New York

Rooftop design will reduce storm water runoff into the East River and support a new beekeeping business benefiting the formerly incarcerated.

"Blue" and "green" detention trays sit side-by-side to slow the flow of stormwater and provide habitat for honey bees.

Source: Hazen and Sawyer
A newly installed roof on top of the Osborne Association building in the South Bronx is projected to manage more than 100,000 gallons of rainwater and will provide habitat for bees that supply honey for the association’s catering business.

The rooftop design, by Hazen and Sawyer, is being promoted as “blue and green” because a water barrier system joins vegetation on the top of the building. Trays for water detention are expected to reduce runoff from the building’s roof area by 32% during a typical storm, helping to mitigate combined sewer overflow into the East River. Other trays holding soil grow vegetation that provides habitat for bee colonies located on an adjacent roof.

The shallow tray design reduced costs and lessened the system’s weight, making it possible to install on the older commercial building. The project covers 7,200 ft2 (668 m2) of the 18,000 ft2 (1,672 m2) roof, according to the Wall Street Journal.

The roof shelters the Osborne Association—an organization that offers services to the formerly incarcerated and their families. Osborne plans to use the roof to launch a honey business in 2014, which will supply honey to its current catering business and expand employment opportunities for former prison inmates. Elizabeth Gaynes, executive director of the Osborne Association, stated in a press release that the combined social and environmental benefits of the project “have resulted in a double bottom line.”

Published September 30, 2013

Pearson, C. (2013, September 30). "Blue Roof" Adds Stormwater Detention Alongside Green Roof in New York. Retrieved from

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