Exploring the Memorial's Sustainable Design on Earth Day

This autumn aerial of the 9/11 Memorial plaza shows the twin reflecting pools, the Museum pavilion, and the dozens of colorful swamp white oak trees that fill the plaza.

(Photo: Courtesy of Port Authority of New York and New Jersey)

The 9/11 Memorial plaza is one of the most sustainable plazas ever constructed, designed to conserve energy, water and other resources.

Rainwater is collected in storage tanks below the plaza surface and the tanks supply water for the nearly 400 trees and vegetation. With hundreds of trees, the plaza is an actual green roof for the 9/11 Memorial Museum located below it. The plaza was built to meet requirements of New York State Executive Order 111, as well as WTC Sustainable Design Guidelines, both of which promote environmentally friendly practices.

The memorial’s urban forest is close by to other green spaces, including Battery Park City, City Hall Park and Liberty Plaza.

The American Society of Landscape Architects describes the Memorial on its website as a “massive green roof – a fully constructed ecology – that operates on top of multiple structures. … The plaza surface-and-drainage infrastructure is designed to function as a large self-sustaining cistern. Water from rainfall and snow melt is channeled into large holding tanks and re-used to support the Memorial forest via a specialized drip-and-spray irrigation system.”