a constructed forest as a living memorial

Alan Ward

Alan Ward


The losses of September 11th are memorialized in this sacred space formed by a dense forest of oak trees, a perfectly flat granite plane, and two gigantic cuts through both, where the names of victims are inscribed in the footprints of the former Twin Towers. Serving as project manager while a partner at PWP Landscape Architecture, Matt Donham advocated tirelessly to achieve the elegant subtlety of the design amidst the unparalleled political and physical complexity of the World Trade Center site. 

Aligned into dramatic colonnades when experienced in the east/west orientation while appearing random in all others, the oaks are a strong formal expression that nonetheless produces significant ecosystem services. The trees reduce the urban heat island, support native bird populations and provide a substantial carbon sink in Lower Manhattan.

The impervious stone surface captures all of the stormwater that falls on the plaza and directs it to cisterns where it is stored to be used for irrigation. A robust engineered soil zone sandwiched between the paved plaza and the structure below is critical to producing horticultural conditions that support the health of the forest and the long-term ecological impact of the project.

Work performed at PWP Landscape Architecture. Collaboration with: Michael AradDavis Brody BondDan Euser WaterArchitecturePaul Cowie & AssociatesFisher Marantz StoneC & G Partners. For more detail on the design visit the New York Times and PWP Landscape Architecture.